* [PATCH net-next 03/10] net: sched: refactor block offloads counter usage
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
Without rtnl lock protection filters can no longer safely manage block
offloads counter themselves. Refactor cls API to protect block offloadcnt
with tcf_block->cb_lock that is already used to protect driver callback
list and nooffloaddevcnt counter. The counter can be modified by concurrent
tasks by new functions that execute block callbacks (which is safe with
previous patch that changed its type to atomic_t), however, block
bind/unbind code that checks the counter value takes cb_lock in write mode
to exclude any concurrent modifications. This approach prevents race
conditions between bind/unbind and callback execution code but allows for
concurrency for tc rule update path.
Move block offload counter, filter in hardware counter and filter flags
management from classifiers into cls hardware offloads API. Make functions
tcf_block_offload_inc() and tcf_block_offload_dec() to be cls API private.
Implement following new cls API to be used instead:
tc_setup_cb_add() - non-destructive filter add. If filter that wasn't
already in hardware is successfully offloaded, increment block offloads
counter, set filter in hardware counter and flag. On failure, previously
offloaded filter is considered to be intact and offloads counter is not
decremented.
tc_setup_cb_replace() - destructive filter replace. Release existing
filter block offload counter and reset its in hardware counter and flag.
Set new filter in hardware counter and flag. On failure, previously
offloaded filter is considered to be destroyed and offload counter is
decremented.
tc_setup_cb_destroy() - filter destroy. Unconditionally decrement block
offloads counter.
Refactor all offload-capable classifiers to atomically offload filters to
hardware, change block offload counter, and set filter in hardware counter
and flag by means of the new cls API functions.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
include/net/pkt_cls.h | 13 +++-
include/net/sch_generic.h | 32 +-------
net/sched/cls_api.c | 155 ++++++++++++++++++++++++++++++++++----
net/sched/cls_bpf.c | 22 +++---
net/sched/cls_flower.c | 23 +++---
net/sched/cls_matchall.c | 15 ++--
net/sched/cls_u32.c | 17 ++---
7 files changed, 193 insertions(+), 84 deletions(-)
diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index 64999ffcb486..a5937fb3c4b2 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -506,7 +506,18 @@ tcf_match_indev(struct sk_buff *skb, int ifindex)
int tc_setup_flow_action(struct flow_action *flow_action,
const struct tcf_exts *exts);
int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
- void *type_data, bool err_stop);
+ void *type_data, bool err_stop, bool rtnl_held);
+int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *flags, unsigned int *in_hw_count, bool rtnl_held);
+int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *old_flags, unsigned int *old_in_hw_count,
+ u32 *new_flags, unsigned int *new_in_hw_count,
+ bool rtnl_held);
+int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *flags, unsigned int *in_hw_count, bool rtnl_held);
unsigned int tcf_exts_num_actions(struct tcf_exts *exts);
struct tc_cls_u32_knode {
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index d778c502decd..373f9476c1de 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -439,36 +439,8 @@ static inline bool lockdep_tcf_proto_is_locked(struct tcf_proto *tp)
#define tcf_proto_dereference(p, tp) \
rcu_dereference_protected(p, lockdep_tcf_proto_is_locked(tp))
-static inline void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
-{
- if (*flags & TCA_CLS_FLAGS_IN_HW)
- return;
- *flags |= TCA_CLS_FLAGS_IN_HW;
- atomic_inc(&block->offloadcnt);
-}
-
-static inline void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
-{
- if (!(*flags & TCA_CLS_FLAGS_IN_HW))
- return;
- *flags &= ~TCA_CLS_FLAGS_IN_HW;
- atomic_dec(&block->offloadcnt);
-}
-
-static inline void
-tc_cls_offload_cnt_update(struct tcf_block *block, u32 *cnt,
- u32 *flags, bool add)
-{
- if (add) {
- if (!*cnt)
- tcf_block_offload_inc(block, flags);
- (*cnt)++;
- } else {
- (*cnt)--;
- if (!*cnt)
- tcf_block_offload_dec(block, flags);
- }
-}
+void tc_cls_offload_cnt_update(struct tcf_block *block, struct tcf_proto *tp,
+ u32 *cnt, u32 *flags, u32 diff, bool add);
static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
{
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 8502bd006b37..4215c849f4a3 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3000,13 +3000,97 @@ int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
}
EXPORT_SYMBOL(tcf_exts_dump_stats);
-int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
- void *type_data, bool err_stop)
+static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
+{
+ if (*flags & TCA_CLS_FLAGS_IN_HW)
+ return;
+ *flags |= TCA_CLS_FLAGS_IN_HW;
+ atomic_inc(&block->offloadcnt);
+}
+
+static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
+{
+ if (!(*flags & TCA_CLS_FLAGS_IN_HW))
+ return;
+ *flags &= ~TCA_CLS_FLAGS_IN_HW;
+ atomic_dec(&block->offloadcnt);
+}
+
+void tc_cls_offload_cnt_update(struct tcf_block *block, struct tcf_proto *tp,
+ u32 *cnt, u32 *flags, u32 diff, bool add)
+{
+ lockdep_assert_held(&block->cb_lock);
+
+ spin_lock(&tp->lock);
+ if (add) {
+ if (!*cnt)
+ tcf_block_offload_inc(block, flags);
+ (*cnt) += diff;
+ } else {
+ (*cnt) -= diff;
+ if (!*cnt)
+ tcf_block_offload_dec(block, flags);
+ }
+ spin_unlock(&tp->lock);
+}
+EXPORT_SYMBOL(tc_cls_offload_cnt_update);
+
+static void
+tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
+ u32 *cnt, u32 *flags)
+{
+ lockdep_assert_held(&block->cb_lock);
+
+ spin_lock(&tp->lock);
+ tcf_block_offload_dec(block, flags);
+ (*cnt) = 0;
+ spin_unlock(&tp->lock);
+}
+
+static int
+__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
+ void *type_data, bool err_stop)
{
struct flow_block_cb *block_cb;
int ok_count = 0;
int err;
+ list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
+ err = block_cb->cb(type, type_data, block_cb->cb_priv);
+ if (err) {
+ if (err_stop)
+ return err;
+ } else {
+ ok_count++;
+ }
+ }
+ return ok_count;
+}
+
+int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
+ void *type_data, bool err_stop, bool rtnl_held)
+{
+ int ok_count;
+
+ down_read(&block->cb_lock);
+ ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
+ up_read(&block->cb_lock);
+ return ok_count;
+}
+EXPORT_SYMBOL(tc_setup_cb_call);
+
+/* Non-destructive filter add. If filter that wasn't already in hardware is
+ * successfully offloaded, increment block offloads counter. On failure,
+ * previously offloaded filter is considered to be intact and offloads counter
+ * is not decremented.
+ */
+
+int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
+{
+ int ok_count;
+
down_read(&block->cb_lock);
/* Make sure all netdevs sharing this block are offload-capable. */
if (block->nooffloaddevcnt && err_stop) {
@@ -3014,22 +3098,67 @@ int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
goto errout;
}
- list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
- err = block_cb->cb(type, type_data, block_cb->cb_priv);
- if (err) {
- if (err_stop) {
- ok_count = err;
- goto errout;
- }
- } else {
- ok_count++;
- }
+ ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
+ if (ok_count > 0)
+ tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
+ ok_count, true);
+errout:
+ up_read(&block->cb_lock);
+ return ok_count;
+}
+EXPORT_SYMBOL(tc_setup_cb_add);
+
+/* Destructive filter replace. If filter that wasn't already in hardware is
+ * successfully offloaded, increment block offload counter. On failure,
+ * previously offloaded filter is considered to be destroyed and offload counter
+ * is decremented.
+ */
+
+int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *old_flags, unsigned int *old_in_hw_count,
+ u32 *new_flags, unsigned int *new_in_hw_count,
+ bool rtnl_held)
+{
+ int ok_count;
+
+ down_read(&block->cb_lock);
+ /* Make sure all netdevs sharing this block are offload-capable. */
+ if (block->nooffloaddevcnt && err_stop) {
+ ok_count = -EOPNOTSUPP;
+ goto errout;
}
+
+ tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
+
+ ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
+ if (ok_count > 0)
+ tc_cls_offload_cnt_update(block, tp, new_in_hw_count, new_flags,
+ ok_count, true);
errout:
up_read(&block->cb_lock);
return ok_count;
}
-EXPORT_SYMBOL(tc_setup_cb_call);
+EXPORT_SYMBOL(tc_setup_cb_replace);
+
+/* Destroy filter and decrement block offload counter, if filter was previously
+ * offloaded.
+ */
+
+int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
+ enum tc_setup_type type, void *type_data, bool err_stop,
+ u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
+{
+ int ok_count;
+
+ down_read(&block->cb_lock);
+ ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
+
+ tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
+ up_read(&block->cb_lock);
+ return ok_count;
+}
+EXPORT_SYMBOL(tc_setup_cb_destroy);
int tc_setup_flow_action(struct flow_action *flow_action,
const struct tcf_exts *exts)
diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c
index 3f7a9c02b70c..7f304db7e697 100644
--- a/net/sched/cls_bpf.c
+++ b/net/sched/cls_bpf.c
@@ -162,17 +162,21 @@ static int cls_bpf_offload_cmd(struct tcf_proto *tp, struct cls_bpf_prog *prog,
cls_bpf.name = obj->bpf_name;
cls_bpf.exts_integrated = obj->exts_integrated;
- if (oldprog)
- tcf_block_offload_dec(block, &oldprog->gen_flags);
+ if (cls_bpf.oldprog)
+ err = tc_setup_cb_replace(block, tp, TC_SETUP_CLSBPF, &cls_bpf,
+ skip_sw, &oldprog->gen_flags,
+ &oldprog->in_hw_count,
+ &prog->gen_flags, &prog->in_hw_count,
+ true);
+ else
+ err = tc_setup_cb_add(block, tp, TC_SETUP_CLSBPF, &cls_bpf,
+ skip_sw, &prog->gen_flags,
+ &prog->in_hw_count, true);
- err = tc_setup_cb_call(block, TC_SETUP_CLSBPF, &cls_bpf, skip_sw);
if (prog) {
if (err < 0) {
cls_bpf_offload_cmd(tp, oldprog, prog, extack);
return err;
- } else if (err > 0) {
- prog->in_hw_count = err;
- tcf_block_offload_inc(block, &prog->gen_flags);
}
}
@@ -230,7 +234,7 @@ static void cls_bpf_offload_update_stats(struct tcf_proto *tp,
cls_bpf.name = prog->bpf_name;
cls_bpf.exts_integrated = prog->exts_integrated;
- tc_setup_cb_call(block, TC_SETUP_CLSBPF, &cls_bpf, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSBPF, &cls_bpf, false, true);
}
static int cls_bpf_init(struct tcf_proto *tp)
@@ -680,8 +684,8 @@ static int cls_bpf_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb
continue;
}
- tc_cls_offload_cnt_update(block, &prog->in_hw_count,
- &prog->gen_flags, add);
+ tc_cls_offload_cnt_update(block, tp, &prog->in_hw_count,
+ &prog->gen_flags, 1, add);
}
return 0;
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 054123742e32..0001a933d48b 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -419,10 +419,10 @@ static void fl_hw_destroy_filter(struct tcf_proto *tp, struct cls_fl_filter *f,
cls_flower.command = FLOW_CLS_DESTROY;
cls_flower.cookie = (unsigned long) f;
- tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false);
+ tc_setup_cb_destroy(block, tp, TC_SETUP_CLSFLOWER, &cls_flower, false,
+ &f->flags, &f->in_hw_count, true);
spin_lock(&tp->lock);
list_del_init(&f->hw_list);
- tcf_block_offload_dec(block, &f->flags);
spin_unlock(&tp->lock);
if (!rtnl_held)
@@ -466,18 +466,15 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
goto errout;
}
- err = tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, skip_sw);
+ err = tc_setup_cb_add(block, tp, TC_SETUP_CLSFLOWER, &cls_flower,
+ skip_sw, &f->flags, &f->in_hw_count, true);
kfree(cls_flower.rule);
if (err < 0) {
fl_hw_destroy_filter(tp, f, true, NULL);
goto errout;
} else if (err > 0) {
- f->in_hw_count = err;
err = 0;
- spin_lock(&tp->lock);
- tcf_block_offload_inc(block, &f->flags);
- spin_unlock(&tp->lock);
}
if (skip_sw && !(f->flags & TCA_CLS_FLAGS_IN_HW)) {
@@ -509,7 +506,7 @@ static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f,
cls_flower.cookie = (unsigned long) f;
cls_flower.classid = f->res.classid;
- tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false, true);
tcf_exts_stats_update(&f->exts, cls_flower.stats.bytes,
cls_flower.stats.pkts,
@@ -1855,10 +1852,8 @@ static int fl_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
goto next_flow;
}
- spin_lock(&tp->lock);
- tc_cls_offload_cnt_update(block, &f->in_hw_count, &f->flags,
- add);
- spin_unlock(&tp->lock);
+ tc_cls_offload_cnt_update(block, tp, &f->in_hw_count, &f->flags,
+ 1, add);
next_flow:
__fl_put(f);
}
@@ -1886,7 +1881,7 @@ static int fl_hw_create_tmplt(struct tcf_chain *chain,
/* We don't care if driver (any of them) fails to handle this
* call. It serves just as a hint for it.
*/
- tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false, true);
kfree(cls_flower.rule);
return 0;
@@ -1902,7 +1897,7 @@ static void fl_hw_destroy_tmplt(struct tcf_chain *chain,
cls_flower.command = FLOW_CLS_TMPLT_DESTROY;
cls_flower.cookie = (unsigned long) tmplt;
- tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false, true);
}
static void *fl_tmplt_create(struct net *net, struct tcf_chain *chain,
diff --git a/net/sched/cls_matchall.c b/net/sched/cls_matchall.c
index 455ea2793f9b..d38e329d71bd 100644
--- a/net/sched/cls_matchall.c
+++ b/net/sched/cls_matchall.c
@@ -75,8 +75,8 @@ static void mall_destroy_hw_filter(struct tcf_proto *tp,
cls_mall.command = TC_CLSMATCHALL_DESTROY;
cls_mall.cookie = cookie;
- tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
- tcf_block_offload_dec(block, &head->flags);
+ tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false, true);
+ head->flags &= ~TCA_CLS_FLAGS_IN_HW;
}
static int mall_replace_hw_filter(struct tcf_proto *tp,
@@ -109,15 +109,13 @@ static int mall_replace_hw_filter(struct tcf_proto *tp,
return err;
}
- err = tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, skip_sw);
+ err = tc_setup_cb_add(block, tp, TC_SETUP_CLSMATCHALL, &cls_mall,
+ skip_sw, &head->flags, &head->in_hw_count, true);
kfree(cls_mall.rule);
if (err < 0) {
mall_destroy_hw_filter(tp, head, cookie, NULL);
return err;
- } else if (err > 0) {
- head->in_hw_count = err;
- tcf_block_offload_inc(block, &head->flags);
}
if (skip_sw && !(head->flags & TCA_CLS_FLAGS_IN_HW))
@@ -321,7 +319,8 @@ static int mall_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
return 0;
}
- tc_cls_offload_cnt_update(block, &head->in_hw_count, &head->flags, add);
+ tc_cls_offload_cnt_update(block, tp, &head->in_hw_count, &head->flags,
+ 1, add);
return 0;
}
@@ -337,7 +336,7 @@ static void mall_stats_hw_filter(struct tcf_proto *tp,
cls_mall.command = TC_CLSMATCHALL_STATS;
cls_mall.cookie = cookie;
- tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSMATCHALL, &cls_mall, false, true);
tcf_exts_stats_update(&head->exts, cls_mall.stats.bytes,
cls_mall.stats.pkts, cls_mall.stats.lastused);
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 8614088edd1b..94c6eca191f9 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -480,7 +480,7 @@ static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
cls_u32.hnode.handle = h->handle;
cls_u32.hnode.prio = h->prio;
- tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false);
+ tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false, true);
}
static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
@@ -498,7 +498,7 @@ static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
cls_u32.hnode.handle = h->handle;
cls_u32.hnode.prio = h->prio;
- err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw);
+ err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw, true);
if (err < 0) {
u32_clear_hw_hnode(tp, h, NULL);
return err;
@@ -522,8 +522,8 @@ static void u32_remove_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
cls_u32.command = TC_CLSU32_DELETE_KNODE;
cls_u32.knode.handle = n->handle;
- tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false);
- tcf_block_offload_dec(block, &n->flags);
+ tc_setup_cb_destroy(block, tp, TC_SETUP_CLSU32, &cls_u32, false,
+ &n->flags, &n->in_hw_count, true);
}
static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
@@ -552,13 +552,11 @@ static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
if (n->ht_down)
cls_u32.knode.link_handle = ht->handle;
- err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw);
+ err = tc_setup_cb_add(block, tp, TC_SETUP_CLSU32, &cls_u32, skip_sw,
+ &n->flags, &n->in_hw_count, true);
if (err < 0) {
u32_remove_hw_knode(tp, n, NULL);
return err;
- } else if (err > 0) {
- n->in_hw_count = err;
- tcf_block_offload_inc(block, &n->flags);
}
if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW))
@@ -1208,7 +1206,8 @@ static int u32_reoffload_knode(struct tcf_proto *tp, struct tc_u_knode *n,
return 0;
}
- tc_cls_offload_cnt_update(block, &n->in_hw_count, &n->flags, add);
+ tc_cls_offload_cnt_update(block, tp, &n->in_hw_count, &n->flags, 1,
+ add);
return 0;
}
--
2.21.0
^ permalink raw reply related
* [PATCH net-next 01/10] net: sched: protect block offload-related fields with rw_semaphore
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
In order to remove dependency on rtnl lock, extend tcf_block with 'cb_lock'
rwsem and use it to protect flow_block->cb_list and related counters from
concurrent modification. The lock is taken in read mode for read-only
traversal of cb_list in tc_setup_cb_call() and write mode in all other
cases. This approach ensures that:
- cb_list is not changed concurrently while filters is being offloaded on
block.
- block->nooffloaddevcnt is checked while holding the lock in read mode,
but is only changed by bind/unbind code when holding the cb_lock in write
mode to prevent concurrent modification.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
include/net/sch_generic.h | 2 ++
net/sched/cls_api.c | 45 +++++++++++++++++++++++++++++++--------
2 files changed, 38 insertions(+), 9 deletions(-)
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index d9f359af0b93..a3eaf5f9d28f 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -13,6 +13,7 @@
#include <linux/refcount.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
+#include <linux/rwsem.h>
#include <net/gen_stats.h>
#include <net/rtnetlink.h>
#include <net/flow_offload.h>
@@ -396,6 +397,7 @@ struct tcf_block {
refcount_t refcnt;
struct net *net;
struct Qdisc *q;
+ struct rw_semaphore cb_lock; /* protects cb_list and offload counters */
struct flow_block flow_block;
struct list_head owner_list;
bool keep_dst;
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index e0d8b456e9f5..a3b07c6e3f53 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -568,9 +568,11 @@ static void tc_indr_block_ing_cmd(struct net_device *dev,
bo.block = &block->flow_block;
+ down_write(&block->cb_lock);
cb(dev, cb_priv, TC_SETUP_BLOCK, &bo);
tcf_block_setup(block, &bo);
+ up_write(&block->cb_lock);
}
static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
@@ -661,6 +663,7 @@ static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
struct net_device *dev = q->dev_queue->dev;
int err;
+ down_write(&block->cb_lock);
if (!dev->netdev_ops->ndo_setup_tc)
goto no_offload_dev_inc;
@@ -669,24 +672,31 @@ static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
*/
if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) {
NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
- return -EOPNOTSUPP;
+ err = -EOPNOTSUPP;
+ goto errout;
}
err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack);
if (err == -EOPNOTSUPP)
goto no_offload_dev_inc;
if (err)
- return err;
+ goto errout;
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
+ up_write(&block->cb_lock);
return 0;
no_offload_dev_inc:
- if (tcf_block_offload_in_use(block))
- return -EOPNOTSUPP;
+ if (tcf_block_offload_in_use(block)) {
+ err = -EOPNOTSUPP;
+ goto errout;
+ }
+ err = 0;
block->nooffloaddevcnt++;
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
- return 0;
+errout:
+ up_write(&block->cb_lock);
+ return err;
}
static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
@@ -695,6 +705,7 @@ static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
struct net_device *dev = q->dev_queue->dev;
int err;
+ down_write(&block->cb_lock);
tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
if (!dev->netdev_ops->ndo_setup_tc)
@@ -702,10 +713,12 @@ static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
if (err == -EOPNOTSUPP)
goto no_offload_dev_dec;
+ up_write(&block->cb_lock);
return;
no_offload_dev_dec:
WARN_ON(block->nooffloaddevcnt-- == 0);
+ up_write(&block->cb_lock);
}
static int
@@ -820,6 +833,7 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
return ERR_PTR(-ENOMEM);
}
mutex_init(&block->lock);
+ init_rwsem(&block->cb_lock);
flow_block_init(&block->flow_block);
INIT_LIST_HEAD(&block->chain_list);
INIT_LIST_HEAD(&block->owner_list);
@@ -1355,6 +1369,8 @@ tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
struct tcf_proto *tp, *tp_prev;
int err;
+ lockdep_assert_held(&block->cb_lock);
+
for (chain = __tcf_get_next_chain(block, NULL);
chain;
chain_prev = chain,
@@ -1393,6 +1409,8 @@ static int tcf_block_bind(struct tcf_block *block,
struct flow_block_cb *block_cb, *next;
int err, i = 0;
+ lockdep_assert_held(&block->cb_lock);
+
list_for_each_entry(block_cb, &bo->cb_list, list) {
err = tcf_block_playback_offloads(block, block_cb->cb,
block_cb->cb_priv, true,
@@ -1427,6 +1445,8 @@ static void tcf_block_unbind(struct tcf_block *block,
{
struct flow_block_cb *block_cb, *next;
+ lockdep_assert_held(&block->cb_lock);
+
list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
tcf_block_playback_offloads(block, block_cb->cb,
block_cb->cb_priv, false,
@@ -2987,19 +3007,26 @@ int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
int ok_count = 0;
int err;
+ down_read(&block->cb_lock);
/* Make sure all netdevs sharing this block are offload-capable. */
- if (block->nooffloaddevcnt && err_stop)
- return -EOPNOTSUPP;
+ if (block->nooffloaddevcnt && err_stop) {
+ ok_count = -EOPNOTSUPP;
+ goto errout;
+ }
list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
err = block_cb->cb(type, type_data, block_cb->cb_priv);
if (err) {
- if (err_stop)
- return err;
+ if (err_stop) {
+ ok_count = err;
+ goto errout;
+ }
} else {
ok_count++;
}
}
+errout:
+ up_read(&block->cb_lock);
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_call);
--
2.21.0
^ permalink raw reply related
* [PATCH net-next 09/10] net: sched: copy tunnel info when setting flow_action entry->tunnel
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
In order to remove dependency on rtnl lock, modify tc_setup_flow_action()
to copy tunnel info, instead of just saving pointer to tunnel_key action
tunnel info. This is necessary to prevent concurrent action overwrite from
releasing tunnel info while it is being used by rtnl-unlocked driver.
Implement helper tcf_tunnel_info_copy() that is used to copy tunnel info
with all its options to dynamically allocated memory block. Modify
tc_cleanup_flow_action() to free dynamically allocated tunnel info.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
include/net/tc_act/tc_tunnel_key.h | 17 +++++++++++++++++
net/sched/cls_api.c | 9 ++++++++-
2 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/include/net/tc_act/tc_tunnel_key.h b/include/net/tc_act/tc_tunnel_key.h
index 7c3f777c168c..0689d9bcdf84 100644
--- a/include/net/tc_act/tc_tunnel_key.h
+++ b/include/net/tc_act/tc_tunnel_key.h
@@ -59,4 +59,21 @@ static inline struct ip_tunnel_info *tcf_tunnel_info(const struct tc_action *a)
return NULL;
#endif
}
+
+static inline struct ip_tunnel_info *
+tcf_tunnel_info_copy(const struct tc_action *a)
+{
+#ifdef CONFIG_NET_CLS_ACT
+ struct ip_tunnel_info *tun = tcf_tunnel_info(a);
+
+ if (tun) {
+ size_t tun_size = sizeof(*tun) + tun->options_len;
+ struct ip_tunnel_info *tun_copy = kmemdup(tun, tun_size,
+ GFP_KERNEL);
+
+ return tun_copy;
+ }
+#endif
+ return NULL;
+}
#endif /* __NET_TC_TUNNEL_KEY_H */
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 96adbff9e845..15423d3a89fd 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3258,6 +3258,9 @@ void tc_cleanup_flow_action(struct flow_action *flow_action)
if (entry->dev)
dev_put(entry->dev);
break;
+ case FLOW_ACTION_TUNNEL_ENCAP:
+ kfree(entry->tunnel);
+ break;
default:
break;
}
@@ -3334,7 +3337,11 @@ int tc_setup_flow_action(struct flow_action *flow_action,
}
} else if (is_tcf_tunnel_set(act)) {
entry->id = FLOW_ACTION_TUNNEL_ENCAP;
- entry->tunnel = tcf_tunnel_info(act);
+ entry->tunnel = tcf_tunnel_info_copy(act);
+ if (!entry->tunnel) {
+ err = -ENOMEM;
+ goto err_out;
+ }
} else if (is_tcf_tunnel_release(act)) {
entry->id = FLOW_ACTION_TUNNEL_DECAP;
} else if (is_tcf_pedit(act)) {
--
2.21.0
^ permalink raw reply related
* [PATCH net-next 00/10] Refactor cls hardware offload API to support rtnl-independent drivers
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev; +Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov
Currently, all cls API hardware offloads driver callbacks require caller
to hold rtnl lock when calling them. This patch set introduces new API
that allows drivers to register callbacks that are not dependent on rtnl
lock and unlocked classifiers to offload filters without obtaining rtnl
lock first, which is intended to allow offloading tc rules in parallel.
Recently, new rtnl registration flag RTNL_FLAG_DOIT_UNLOCKED was added.
TC rule update handlers (RTM_NEWTFILTER, RTM_DELTFILTER, etc.) are
already registered with this flag and only take rtnl lock when qdisc or
classifier requires it. Classifiers can indicate that their ops
callbacks don't require caller to hold rtnl lock by setting the
TCF_PROTO_OPS_DOIT_UNLOCKED flag. Unlocked implementation of flower
classifier is now upstreamed. However, this implementation still obtains
rtnl lock before calling hardware offloads API.
Implement following cls API changes:
- Introduce new "unlocked_driver_cb" flag to struct flow_block_offload
to allow registering and unregistering block hardware offload
callbacks that do not require caller to hold rtnl lock. Drivers that
doesn't require users of its tc offload callbacks to hold rtnl lock
sets the flag to true on block bind/unbind. Internally tcf_block is
extended with additional lockeddevcnt counter that is used to count
number of devices that require rtnl lock that block is bound to. When
this counter is zero, tc_setup_cb_*() functions execute callbacks
without obtaining rtnl lock.
- Extend cls API single hardware rule update tc_setup_cb_call() function
with tc_setup_cb_add(), tc_setup_cb_replace() and
tc_setup_cb_destroy() functions. These new APIs are needed to move
management of block offload counter, filter in hardware counter and
flag from classifier implementations to cls API, which is now
responsible for managing them in concurrency-safe manner. Access to
cb_list from callback execution code is synchronized by obtaining new
'cb_lock' rw_semaphore in read mode, which allows executing callbacks
in parallel, but excludes any modifications of data from
register/unregister code. tcf_block offloads counter type is changed
to atomic integer to allow updating the counter concurrently.
- Extend classifier ops with new ops->hw_add() and ops->hw_del()
callbacks which are used to notify unlocked classifiers when filter is
successfully added or deleted to hardware without releasing cb_lock.
This is necessary to update classifier state atomically with callback
list traversal and updating of all relevant counters and allows
unlocked classifiers to synchronize with concurrent reoffload without
requiring any changes to driver callback API implementations.
New tc flow_action infrastructure is also modified to allow its user to
execute without rtnl lock protection. Function tc_setup_flow_action() is
modified to conditionally obtain rtnl lock before accessing action
state. Action data that is accessed by reference is either copied or
reference counted to prevent concurrent action overwrite from
deallocating it. New function tc_cleanup_flow_action() is introduced to
cleanup/release all such data obtained by tc_setup_flow_action().
Flower classifier (only unlocked classifier at the moment) is modified
to use new cls hardware offloads API and no longer obtains rtnl lock
before calling it.
Vlad Buslov (10):
net: sched: protect block offload-related fields with rw_semaphore
net: sched: change tcf block offload counter type to atomic_t
net: sched: refactor block offloads counter usage
net: sched: notify classifier on successful offload add/delete
net: sched: add API for registering unlocked offload block callbacks
net: sched: conditionally obtain rtnl lock in cls hw offloads API
net: sched: take rtnl lock in tc_setup_flow_action()
net: sched: take reference to action dev before calling offloads
net: sched: copy tunnel info when setting flow_action entry->tunnel
net: sched: flower: don't take rtnl lock for cls hw offloads API
.../net/ethernet/mellanox/mlx5/core/en_main.c | 2 +
.../net/ethernet/mellanox/mlx5/core/en_rep.c | 3 +
include/net/flow_offload.h | 1 +
include/net/pkt_cls.h | 17 +-
include/net/sch_generic.h | 42 +--
include/net/tc_act/tc_tunnel_key.h | 17 +
net/sched/cls_api.c | 322 +++++++++++++++++-
net/sched/cls_bpf.c | 22 +-
net/sched/cls_flower.c | 111 +++---
net/sched/cls_matchall.c | 19 +-
net/sched/cls_u32.c | 17 +-
11 files changed, 437 insertions(+), 136 deletions(-)
--
2.21.0
^ permalink raw reply
* [PATCH net-next 06/10] net: sched: conditionally obtain rtnl lock in cls hw offloads API
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
In order to remove dependency on rtnl lock from offloads code of
classifiers, take rtnl lock conditionally before executing driver
callbacks. Only obtain rtnl lock if block is bound to devices that require
it.
Block bind/unbind code is rtnl-locked and obtains block->cb_lock while
holding rtnl lock. Obtain locks in same order in tc_setup_cb_*() functions
to prevent deadlock.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
net/sched/cls_api.c | 65 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 65 insertions(+)
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 02a547aa77c0..bda42f1b5514 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3076,11 +3076,28 @@ __tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
void *type_data, bool err_stop, bool rtnl_held)
{
+ bool take_rtnl = false;
int ok_count;
+retry:
+ if (take_rtnl)
+ rtnl_lock();
down_read(&block->cb_lock);
+ /* Need to obtain rtnl lock if block is bound to devs that require it.
+ * In block bind code cb_lock is obtained while holding rtnl, so we must
+ * obtain the locks in same order here.
+ */
+ if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
+ up_read(&block->cb_lock);
+ take_rtnl = true;
+ goto retry;
+ }
+
ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
+
up_read(&block->cb_lock);
+ if (take_rtnl)
+ rtnl_unlock();
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_call);
@@ -3095,9 +3112,23 @@ int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
enum tc_setup_type type, void *type_data, bool err_stop,
u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
{
+ bool take_rtnl = false;
int ok_count;
+retry:
+ if (take_rtnl)
+ rtnl_lock();
down_read(&block->cb_lock);
+ /* Need to obtain rtnl lock if block is bound to devs that require it.
+ * In block bind code cb_lock is obtained while holding rtnl, so we must
+ * obtain the locks in same order here.
+ */
+ if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
+ up_read(&block->cb_lock);
+ take_rtnl = true;
+ goto retry;
+ }
+
/* Make sure all netdevs sharing this block are offload-capable. */
if (block->nooffloaddevcnt && err_stop) {
ok_count = -EOPNOTSUPP;
@@ -3114,6 +3145,8 @@ int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
}
errout:
up_read(&block->cb_lock);
+ if (take_rtnl)
+ rtnl_unlock();
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_add);
@@ -3130,9 +3163,23 @@ int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
u32 *new_flags, unsigned int *new_in_hw_count,
bool rtnl_held)
{
+ bool take_rtnl = false;
int ok_count;
+retry:
+ if (take_rtnl)
+ rtnl_lock();
down_read(&block->cb_lock);
+ /* Need to obtain rtnl lock if block is bound to devs that require it.
+ * In block bind code cb_lock is obtained while holding rtnl, so we must
+ * obtain the locks in same order here.
+ */
+ if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
+ up_read(&block->cb_lock);
+ take_rtnl = true;
+ goto retry;
+ }
+
/* Make sure all netdevs sharing this block are offload-capable. */
if (block->nooffloaddevcnt && err_stop) {
ok_count = -EOPNOTSUPP;
@@ -3153,6 +3200,8 @@ int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
}
errout:
up_read(&block->cb_lock);
+ if (take_rtnl)
+ rtnl_unlock();
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_replace);
@@ -3165,9 +3214,23 @@ int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
enum tc_setup_type type, void *type_data, bool err_stop,
u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
{
+ bool take_rtnl = false;
int ok_count;
+retry:
+ if (take_rtnl)
+ rtnl_lock();
down_read(&block->cb_lock);
+ /* Need to obtain rtnl lock if block is bound to devs that require it.
+ * In block bind code cb_lock is obtained while holding rtnl, so we must
+ * obtain the locks in same order here.
+ */
+ if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
+ up_read(&block->cb_lock);
+ take_rtnl = true;
+ goto retry;
+ }
+
ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
@@ -3175,6 +3238,8 @@ int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
tp->ops->hw_del(tp, type_data);
up_read(&block->cb_lock);
+ if (take_rtnl)
+ rtnl_unlock();
return ok_count;
}
EXPORT_SYMBOL(tc_setup_cb_destroy);
--
2.21.0
^ permalink raw reply related
* [PATCH net-next 05/10] net: sched: add API for registering unlocked offload block callbacks
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
Extend struct flow_block_offload with "unlocked_driver_cb" flag to allow
registering and unregistering block hardware offload callbacks that do not
require caller to hold rtnl lock. Extend tcf_block with additional
lockeddevcnt counter that is incremented for each non-unlocked driver
callback attached to device. This counter is necessary to conditionally
obtain rtnl lock before calling hardware callbacks in following patches.
Register mlx5 tc block offload callbacks as "unlocked".
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 2 ++
drivers/net/ethernet/mellanox/mlx5/core/en_rep.c | 3 +++
include/net/flow_offload.h | 1 +
include/net/sch_generic.h | 1 +
net/sched/cls_api.c | 6 ++++++
5 files changed, 13 insertions(+)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 7fdea6479ff6..8abdef1f8470 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -3469,10 +3469,12 @@ static int mlx5e_setup_tc(struct net_device *dev, enum tc_setup_type type,
void *type_data)
{
struct mlx5e_priv *priv = netdev_priv(dev);
+ struct flow_block_offload *f = type_data;
switch (type) {
#ifdef CONFIG_MLX5_ESWITCH
case TC_SETUP_BLOCK:
+ f->unlocked_driver_cb = true;
return flow_block_cb_setup_simple(type_data,
&mlx5e_block_cb_list,
mlx5e_setup_tc_block_cb,
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
index 3c0d36b2b91c..e7ac6233037d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
@@ -763,6 +763,7 @@ mlx5e_rep_indr_setup_tc_block(struct net_device *netdev,
if (f->binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS)
return -EOPNOTSUPP;
+ f->unlocked_driver_cb = true;
f->driver_block_list = &mlx5e_block_cb_list;
switch (f->command) {
@@ -1245,9 +1246,11 @@ static int mlx5e_rep_setup_tc(struct net_device *dev, enum tc_setup_type type,
void *type_data)
{
struct mlx5e_priv *priv = netdev_priv(dev);
+ struct flow_block_offload *f = type_data;
switch (type) {
case TC_SETUP_BLOCK:
+ f->unlocked_driver_cb = true;
return flow_block_cb_setup_simple(type_data,
&mlx5e_rep_block_cb_list,
mlx5e_rep_setup_tc_cb,
diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index 757fa84de654..fc881875f856 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -284,6 +284,7 @@ struct flow_block_offload {
enum flow_block_command command;
enum flow_block_binder_type binder_type;
bool block_shared;
+ bool unlocked_driver_cb;
struct net *net;
struct flow_block *block;
struct list_head cb_list;
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 4ad43335cae5..d0c282e3630b 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -408,6 +408,7 @@ struct tcf_block {
bool keep_dst;
atomic_t offloadcnt; /* Number of oddloaded filters */
unsigned int nooffloaddevcnt; /* Number of devs unable to do offload */
+ unsigned int lockeddevcnt; /* Number of devs that require rtnl lock. */
struct {
struct tcf_chain *chain;
struct list_head filter_chain_list;
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index d8ef7a9e6906..02a547aa77c0 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1418,6 +1418,8 @@ static int tcf_block_bind(struct tcf_block *block,
bo->extack);
if (err)
goto err_unroll;
+ if (!bo->unlocked_driver_cb)
+ block->lockeddevcnt++;
i++;
}
@@ -1433,6 +1435,8 @@ static int tcf_block_bind(struct tcf_block *block,
block_cb->cb_priv, false,
tcf_block_offload_in_use(block),
NULL);
+ if (!bo->unlocked_driver_cb)
+ block->lockeddevcnt--;
}
flow_block_cb_free(block_cb);
}
@@ -1454,6 +1458,8 @@ static void tcf_block_unbind(struct tcf_block *block,
NULL);
list_del(&block_cb->list);
flow_block_cb_free(block_cb);
+ if (!bo->unlocked_driver_cb)
+ block->lockeddevcnt--;
}
}
--
2.21.0
^ permalink raw reply related
* [PATCH net-next 04/10] net: sched: notify classifier on successful offload add/delete
From: Vlad Buslov @ 2019-08-22 12:43 UTC (permalink / raw)
To: netdev
Cc: jhs, xiyou.wangcong, jiri, davem, jakub.kicinski, pablo,
Vlad Buslov, Jiri Pirko
In-Reply-To: <20190822124353.16902-1-vladbu@mellanox.com>
To remove dependency on rtnl lock, extend classifier ops with new
ops->hw_add() and ops->hw_del() callbacks. Call them from cls API while
holding cb_lock every time filter if successfully added to or deleted from
hardware.
Implement the new API in flower classifier. Use it to manage hw_filters
list under cb_lock protection, instead of relying on rtnl lock to
synchronize with concurrent fl_reoffload() call.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
---
include/net/sch_generic.h | 4 ++++
net/sched/cls_api.c | 25 +++++++++++++++++++------
net/sched/cls_flower.c | 33 ++++++++++++++++++++++++++-------
3 files changed, 49 insertions(+), 13 deletions(-)
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 373f9476c1de..4ad43335cae5 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -312,6 +312,10 @@ struct tcf_proto_ops {
int (*reoffload)(struct tcf_proto *tp, bool add,
flow_setup_cb_t *cb, void *cb_priv,
struct netlink_ext_ack *extack);
+ void (*hw_add)(struct tcf_proto *tp,
+ void *type_data);
+ void (*hw_del)(struct tcf_proto *tp,
+ void *type_data);
void (*bind_class)(void *, u32, unsigned long);
void * (*tmplt_create)(struct net *net,
struct tcf_chain *chain,
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 4215c849f4a3..d8ef7a9e6906 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3099,9 +3099,13 @@ int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
}
ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
- if (ok_count > 0)
- tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
- ok_count, true);
+ if (ok_count >= 0) {
+ if (tp->ops->hw_add)
+ tp->ops->hw_add(tp, type_data);
+ if (ok_count > 0)
+ tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
+ ok_count, true);
+ }
errout:
up_read(&block->cb_lock);
return ok_count;
@@ -3130,11 +3134,17 @@ int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
}
tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
+ if (tp->ops->hw_del)
+ tp->ops->hw_del(tp, type_data);
ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
- if (ok_count > 0)
- tc_cls_offload_cnt_update(block, tp, new_in_hw_count, new_flags,
- ok_count, true);
+ if (ok_count >= 0) {
+ if (tp->ops->hw_add)
+ tp->ops->hw_add(tp, type_data);
+ if (ok_count > 0)
+ tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
+ new_flags, ok_count, true);
+ }
errout:
up_read(&block->cb_lock);
return ok_count;
@@ -3155,6 +3165,9 @@ int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
+ if (tp->ops->hw_del)
+ tp->ops->hw_del(tp, type_data);
+
up_read(&block->cb_lock);
return ok_count;
}
diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c
index 0001a933d48b..cd1686a5abe7 100644
--- a/net/sched/cls_flower.c
+++ b/net/sched/cls_flower.c
@@ -421,9 +421,6 @@ static void fl_hw_destroy_filter(struct tcf_proto *tp, struct cls_fl_filter *f,
tc_setup_cb_destroy(block, tp, TC_SETUP_CLSFLOWER, &cls_flower, false,
&f->flags, &f->in_hw_count, true);
- spin_lock(&tp->lock);
- list_del_init(&f->hw_list);
- spin_unlock(&tp->lock);
if (!rtnl_held)
rtnl_unlock();
@@ -433,7 +430,6 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
struct cls_fl_filter *f, bool rtnl_held,
struct netlink_ext_ack *extack)
{
- struct cls_fl_head *head = fl_head_dereference(tp);
struct tcf_block *block = tp->chain->block;
struct flow_cls_offload cls_flower = {};
bool skip_sw = tc_skip_sw(f->flags);
@@ -482,9 +478,6 @@ static int fl_hw_replace_filter(struct tcf_proto *tp,
goto errout;
}
- spin_lock(&tp->lock);
- list_add(&f->hw_list, &head->hw_filters);
- spin_unlock(&tp->lock);
errout:
if (!rtnl_held)
rtnl_unlock();
@@ -1861,6 +1854,30 @@ static int fl_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
return 0;
}
+static void fl_hw_add(struct tcf_proto *tp, void *type_data)
+{
+ struct flow_cls_offload *cls_flower = type_data;
+ struct cls_fl_filter *f =
+ (struct cls_fl_filter *) cls_flower->cookie;
+ struct cls_fl_head *head = fl_head_dereference(tp);
+
+ spin_lock(&tp->lock);
+ list_add(&f->hw_list, &head->hw_filters);
+ spin_unlock(&tp->lock);
+}
+
+static void fl_hw_del(struct tcf_proto *tp, void *type_data)
+{
+ struct flow_cls_offload *cls_flower = type_data;
+ struct cls_fl_filter *f =
+ (struct cls_fl_filter *) cls_flower->cookie;
+
+ spin_lock(&tp->lock);
+ if (!list_empty(&f->hw_list))
+ list_del_init(&f->hw_list);
+ spin_unlock(&tp->lock);
+}
+
static int fl_hw_create_tmplt(struct tcf_chain *chain,
struct fl_flow_tmplt *tmplt)
{
@@ -2521,6 +2538,8 @@ static struct tcf_proto_ops cls_fl_ops __read_mostly = {
.delete = fl_delete,
.walk = fl_walk,
.reoffload = fl_reoffload,
+ .hw_add = fl_hw_add,
+ .hw_del = fl_hw_del,
.dump = fl_dump,
.bind_class = fl_bind_class,
.tmplt_create = fl_tmplt_create,
--
2.21.0
^ permalink raw reply related
* Re: [PATCH] Staging: isdn/gigaset : Fix bare unsigned warnings and trailing lines errors
From: Dan Carpenter @ 2019-08-22 12:42 UTC (permalink / raw)
To: Martin Tomes; +Cc: isdn, devel, gregkh, linux-kernel, netdev
In-Reply-To: <1566401259-16921-1-git-send-email-tomesm@gmail.com>
Hi Martin,
These drivers are ancient and going to be deleted soon. We're not
accepting cleanups for them at this point.
On Wed, Aug 21, 2019 at 03:27:39PM +0000, Martin Tomes wrote:
> There are many bare use of unsigned warnings and trailing statements should be on next line errors from checkpatch.pl script.
> Change the code by adding 'unsigned int'. Move 'break' statement of 'switch' command to next line.
For future reference, this should be split up so each patch fixes
one kind of style issue. And the commit message lines of text are too
long. The limit is 75 characters for commit messages (like an email).
regards,
dan carpenter
^ permalink raw reply
* [PATCH] Staging: isdn/gigaset : Fix bare unsigned warnings and trailing lines errors
From: Martin Tomes @ 2019-08-21 15:27 UTC (permalink / raw)
To: isdn; +Cc: gregkh, linux-kernel, devel, netdev, Martin Tomes
There are many bare use of unsigned warnings and trailing statements should be on next line errors from checkpatch.pl script.
Change the code by adding 'unsigned int'. Move 'break' statement of 'switch' command to next line.
Signed-off-by: Martin Tomes <tomesm@gmail.com>
---
drivers/staging/isdn/gigaset/usb-gigaset.c | 52 ++++++++++++++++++------------
1 file changed, 31 insertions(+), 21 deletions(-)
diff --git a/drivers/staging/isdn/gigaset/usb-gigaset.c b/drivers/staging/isdn/gigaset/usb-gigaset.c
index 1b9b436..d565242 100644
--- a/drivers/staging/isdn/gigaset/usb-gigaset.c
+++ b/drivers/staging/isdn/gigaset/usb-gigaset.c
@@ -143,16 +143,16 @@ struct usb_cardstate {
char bchars[6]; /* for request 0x19 */
};
-static inline unsigned tiocm_to_gigaset(unsigned state)
+static inline unsigned int tiocm_to_gigaset(unsigned int state)
{
return ((state & TIOCM_DTR) ? 1 : 0) | ((state & TIOCM_RTS) ? 2 : 0);
}
-static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned old_state,
- unsigned new_state)
+static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned int old_state,
+ unsigned int new_state)
{
struct usb_device *udev = cs->hw.usb->udev;
- unsigned mask, val;
+ unsigned int mask, val;
int r;
mask = tiocm_to_gigaset(old_state ^ new_state);
@@ -178,7 +178,7 @@ static int set_value(struct cardstate *cs, u8 req, u16 val)
int r, r2;
gig_dbg(DEBUG_USBREQ, "request %02x (%04x)",
- (unsigned)req, (unsigned)val);
+ (unsigned int)req, (unsigned int)val);
r = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0x12, 0x41,
0xf /*?*/, 0, NULL, 0, 2000 /*?*/);
/* no idea what this does */
@@ -191,7 +191,7 @@ static int set_value(struct cardstate *cs, u8 req, u16 val)
val, 0, NULL, 0, 2000 /*?*/);
if (r < 0)
dev_err(&udev->dev, "error %d on request 0x%02x\n",
- -r, (unsigned)req);
+ -r, (unsigned int)req);
r2 = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), 0x19, 0x41,
0, 0, cs->hw.usb->bchars, 6, 2000 /*?*/);
@@ -205,7 +205,7 @@ static int set_value(struct cardstate *cs, u8 req, u16 val)
* set the baud rate on the internal serial adapter
* using the undocumented parameter setting command
*/
-static int gigaset_baud_rate(struct cardstate *cs, unsigned cflag)
+static int gigaset_baud_rate(struct cardstate *cs, unsigned int cflag)
{
u16 val;
u32 rate;
@@ -213,16 +213,26 @@ static int gigaset_baud_rate(struct cardstate *cs, unsigned cflag)
cflag &= CBAUD;
switch (cflag) {
- case B300: rate = 300; break;
- case B600: rate = 600; break;
- case B1200: rate = 1200; break;
- case B2400: rate = 2400; break;
- case B4800: rate = 4800; break;
- case B9600: rate = 9600; break;
- case B19200: rate = 19200; break;
- case B38400: rate = 38400; break;
- case B57600: rate = 57600; break;
- case B115200: rate = 115200; break;
+ case B300: rate = 300;
+ break;
+ case B600: rate = 600;
+ break;
+ case B1200: rate = 1200;
+ break;
+ case B2400: rate = 2400;
+ break;
+ case B4800: rate = 4800;
+ break;
+ case B9600: rate = 9600;
+ break;
+ case B19200: rate = 19200;
+ break;
+ case B38400: rate = 38400;
+ break;
+ case B57600: rate = 57600;
+ break;
+ case B115200: rate = 115200;
+ break;
default:
rate = 9600;
dev_err(cs->dev, "unsupported baudrate request 0x%x,"
@@ -345,7 +355,7 @@ static void gigaset_read_int_callback(struct urb *urb)
struct inbuf_t *inbuf = cs->inbuf;
int status = urb->status;
int r;
- unsigned numbytes;
+ unsigned int numbytes;
unsigned char *src;
unsigned long flags;
@@ -357,7 +367,7 @@ static void gigaset_read_int_callback(struct urb *urb)
if (unlikely(*src))
dev_warn(cs->dev,
"%s: There was no leading 0, but 0x%02x!\n",
- __func__, (unsigned) *src);
+ __func__, (unsigned int) *src);
++src; /* skip leading 0x00 */
--numbytes;
if (gigaset_fill_inbuf(inbuf, src, numbytes)) {
@@ -517,7 +527,7 @@ static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb)
static int gigaset_write_room(struct cardstate *cs)
{
- unsigned bytes;
+ unsigned int bytes;
bytes = cs->cmdbytes;
return bytes < IF_WRITEBUF ? IF_WRITEBUF - bytes : 0;
@@ -611,7 +621,7 @@ static int write_modem(struct cardstate *cs)
}
/* Copy data to bulk out buffer and transmit data */
- count = min(bcs->tx_skb->len, (unsigned) ucs->bulk_out_size);
+ count = min(bcs->tx_skb->len, (unsigned int) ucs->bulk_out_size);
skb_copy_from_linear_data(bcs->tx_skb, ucs->bulk_out_buffer, count);
skb_pull(bcs->tx_skb, count);
ucs->busy = 1;
--
1.8.3.1
^ permalink raw reply related
* Re: [RFC bpf-next 4/5] iproute2: Allow compiling against libbpf
From: Daniel Borkmann @ 2019-08-22 12:33 UTC (permalink / raw)
To: Toke Høiland-Jørgensen, Stephen Hemminger,
Alexei Starovoitov
Cc: Martin KaFai Lau, Song Liu, Yonghong Song, David Miller,
Jesper Dangaard Brouer, netdev, bpf, andrii.nakryiko
In-Reply-To: <877e75pftb.fsf@toke.dk>
On 8/22/19 2:04 PM, Toke Høiland-Jørgensen wrote:
> Daniel Borkmann <daniel@iogearbox.net> writes:
>> On 8/22/19 12:43 PM, Toke Høiland-Jørgensen wrote:
>>> Daniel Borkmann <daniel@iogearbox.net> writes:
>>>> On 8/20/19 1:47 PM, Toke Høiland-Jørgensen wrote:
>>>>> This adds a configure check for libbpf and renames functions to allow
>>>>> lib/bpf.c to be compiled with it present. This makes it possible to
>>>>> port functionality piecemeal to use libbpf.
>>>>>
>>>>> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
>>>>> ---
>>>>> configure | 16 ++++++++++++++++
>>>>> include/bpf_util.h | 6 +++---
>>>>> ip/ipvrf.c | 4 ++--
>>>>> lib/bpf.c | 33 +++++++++++++++++++--------------
>>>>> 4 files changed, 40 insertions(+), 19 deletions(-)
>>>>>
>>>>> diff --git a/configure b/configure
>>>>> index 45fcffb6..5a89ee9f 100755
>>>>> --- a/configure
>>>>> +++ b/configure
>>>>> @@ -238,6 +238,19 @@ check_elf()
>>>>> fi
>>>>> }
>>>>>
>>>>> +check_libbpf()
>>>>> +{
>>>>> + if ${PKG_CONFIG} libbpf --exists; then
>>>>> + echo "HAVE_LIBBPF:=y" >>$CONFIG
>>>>> + echo "yes"
>>>>> +
>>>>> + echo 'CFLAGS += -DHAVE_LIBBPF' `${PKG_CONFIG} libbpf --cflags` >> $CONFIG
>>>>> + echo 'LDLIBS += ' `${PKG_CONFIG} libbpf --libs` >>$CONFIG
>>>>> + else
>>>>> + echo "no"
>>>>> + fi
>>>>> +}
>>>>> +
>>>>> check_selinux()
>>>>
>>>> More of an implementation detail at this point in time, but want to
>>>> make sure this doesn't get missed along the way: as discussed at
>>>> bpfconf [0] best for iproute2 to handle libbpf support would be the
>>>> same way of integration as pahole does, that is, to integrate it via
>>>> submodule [1] to allow kernel and libbpf features to be in sync with
>>>> iproute2 releases and therefore easily consume extensions we're adding
>>>> to libbpf to aide iproute2 integration.
>>>
>>> I can sorta see the point wrt keeping in sync with kernel features. But
>>> how will this work with distros that package libbpf as a regular
>>> library? Have you guys given up on regular library symbol versioning for
>>> libbpf?
>>
>> Not at all, and I hope you know that. ;-)
>
> Good! Didn't really expect you had, just checking ;)
>
>> The reason I added lib/bpf.c integration into iproute2 directly back
>> then was exactly such that users can start consuming BPF for tc and
>> XDP via iproute2 /everywhere/ with only a simple libelf dependency
>> which is also available on all distros since pretty much forever. If
>> it was an external library, we could have waited till hell freezes
>> over and initial distro adoption would have pretty much taken forever:
>> to pick one random example here wrt the pace of some downstream
>> distros [0]. The main rationale is pretty much the same as with added
>> kernel features that land complementary iproute2 patches for that
>> kernel release and as libbpf is developed alongside it is reasonable
>> to guarantee user expectations that iproute2 released for kernel
>> version x can make use of BPF features added to kernel x with same
>> loader support from x.
>
> Well, for iproute2 I would expect this to be solved by version
> dependencies. I.e. iproute2 version X would depend on libbpf version Y+
> (like, I dunno, the version of libbpf included in the same kernel source
> tree as the kernel version iproute2 is targeting? :)).
This sounds nice in theory, but from what I've seen major (!) distros
already seem to have a hard time releasing kernel x along with iproute2
package x, concrete example was that distro kernel was on 4.13 and its
official iproute2 package on 4.9, adding yet another variable that needs
to be in sync with kernel is simply impractical especially for a _core_
package like iproute2 that should have as little dependencies as possible.
I also don't want to make a bet on whether libbpf will be available on
every distro that also ships iproute2. Hence approach that pahole (and
also bcc by the way) takes is most reasonable to have the best user
experience.
Thanks,
Daniel
^ permalink raw reply
* 答复: [PATCH][net-next] net: drop_monitor: change the stats variable to u64 in net_dm_stats_put
From: Li,Rongqing @ 2019-08-22 12:31 UTC (permalink / raw)
To: Ido Schimmel; +Cc: netdev@vger.kernel.org, idosch@mellanox.com
In-Reply-To: <20190822115946.GA25090@splinter>
> -----邮件原件-----
> 发件人: Ido Schimmel [mailto:idosch@idosch.org]
> 发送时间: 2019年8月22日 20:00
> 收件人: Li,Rongqing <lirongqing@baidu.com>
> 抄送: netdev@vger.kernel.org; idosch@mellanox.com
> 主题: Re: [PATCH][net-next] net: drop_monitor: change the stats variable to
> u64 in net_dm_stats_put
>
> On Thu, Aug 22, 2019 at 02:22:33PM +0800, Li RongQing wrote:
> > only the element drop of struct net_dm_stats is used, so simplify it
> > to u64
>
> Thanks for the patch, but I don't really see the value here. The struct allows for
> easy extensions in the future. What do you gain from this change? We merely
> read stats and report them to user space, so I guess it's not about
> performance either.
>
I think u64 can reduce to call memset and dereference stats.drop
If it is for future, keep it
-RongQing
^ permalink raw reply
* [PATCH net v2] ixgbe: fix double clean of tx descriptors with xdp
From: Ilya Maximets @ 2019-08-22 12:30 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, bpf, David S. Miller, Björn Töpel,
Magnus Karlsson, Jakub Kicinski, Alexei Starovoitov,
Daniel Borkmann, Jeff Kirsher, intel-wired-lan, Eelco Chaudron,
William Tu, Alexander Duyck, Ilya Maximets
In-Reply-To: <CGME20190822123045eucas1p125b6e106f0310bdb50e759ef41993a91@eucas1p1.samsung.com>
Tx code doesn't clear the descriptors' status after cleaning.
So, if the budget is larger than number of used elems in a ring, some
descriptors will be accounted twice and xsk_umem_complete_tx will move
prod_tail far beyond the prod_head breaking the comletion queue ring.
Fix that by limiting the number of descriptors to clean by the number
of used descriptors in the tx ring.
'ixgbe_clean_xdp_tx_irq()' function refactored to look more like
'ixgbe_xsk_clean_tx_ring()' since we don't need most of the
complications implemented in the regular 'ixgbe_clean_tx_irq()'
and we're allowed to directly use 'next_to_clean' and 'next_to_use'
indexes.
Fixes: 8221c5eba8c1 ("ixgbe: add AF_XDP zero-copy Tx support")
Signed-off-by: Ilya Maximets <i.maximets@samsung.com>
---
Version 2:
* 'ixgbe_clean_xdp_tx_irq()' refactored to look more like
'ixgbe_xsk_clean_tx_ring()'.
drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c | 34 ++++++++------------
1 file changed, 13 insertions(+), 21 deletions(-)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
index 6b609553329f..d1297660e14a 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_xsk.c
@@ -633,22 +633,23 @@ static void ixgbe_clean_xdp_tx_buffer(struct ixgbe_ring *tx_ring,
bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector,
struct ixgbe_ring *tx_ring, int napi_budget)
{
+ u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
unsigned int total_packets = 0, total_bytes = 0;
- u32 i = tx_ring->next_to_clean, xsk_frames = 0;
unsigned int budget = q_vector->tx.work_limit;
struct xdp_umem *umem = tx_ring->xsk_umem;
- union ixgbe_adv_tx_desc *tx_desc;
- struct ixgbe_tx_buffer *tx_bi;
+ u32 xsk_frames = 0;
bool xmit_done;
- tx_bi = &tx_ring->tx_buffer_info[i];
- tx_desc = IXGBE_TX_DESC(tx_ring, i);
- i -= tx_ring->count;
+ while (likely(ntc != ntu && budget)) {
+ union ixgbe_adv_tx_desc *tx_desc;
+ struct ixgbe_tx_buffer *tx_bi;
+
+ tx_desc = IXGBE_TX_DESC(tx_ring, ntc);
- do {
if (!(tx_desc->wb.status & cpu_to_le32(IXGBE_TXD_STAT_DD)))
break;
+ tx_bi = &tx_ring->tx_buffer_info[ntc];
total_bytes += tx_bi->bytecount;
total_packets += tx_bi->gso_segs;
@@ -659,24 +660,15 @@ bool ixgbe_clean_xdp_tx_irq(struct ixgbe_q_vector *q_vector,
tx_bi->xdpf = NULL;
- tx_bi++;
- tx_desc++;
- i++;
- if (unlikely(!i)) {
- i -= tx_ring->count;
- tx_bi = tx_ring->tx_buffer_info;
- tx_desc = IXGBE_TX_DESC(tx_ring, 0);
- }
-
- /* issue prefetch for next Tx descriptor */
- prefetch(tx_desc);
+ ntc++;
+ if (unlikely(ntc == tx_ring->count))
+ ntc = 0;
/* update budget accounting */
budget--;
- } while (likely(budget));
+ }
- i += tx_ring->count;
- tx_ring->next_to_clean = i;
+ tx_ring->next_to_clean = ntc;
u64_stats_update_begin(&tx_ring->syncp);
tx_ring->stats.bytes += total_bytes;
--
2.17.1
^ permalink raw reply related
* [PATCH net] rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up
From: David Howells @ 2019-08-22 12:26 UTC (permalink / raw)
To: netdev; +Cc: dhowells, marc.dionne, linux-afs, linux-kernel
When a local endpoint is ceases to be in use, such as when the kafs module
is unloaded, the kernel will emit an assertion failure if there are any
outstanding client connections:
rxrpc: Assertion failed
------------[ cut here ]------------
kernel BUG at net/rxrpc/local_object.c:433!
and even beyond that, will evince other oopses if there are service
connections still present.
Fix this by:
(1) Removing the triggering of connection reaping when an rxrpc socket is
released. These don't actually clean up the connections anyway - and
further, the local endpoint may still be in use through another
socket.
(2) Mark the local endpoint as dead when we start the process of tearing
it down.
(3) When destroying a local endpoint, strip all of its client connections
from the idle list and discard the ref on each that the list was
holding.
(4) When destroying a local endpoint, call the service connection reaper
directly (rather than through a workqueue) to immediately kill off all
outstanding service connections.
(5) Make the service connection reaper reap connections for which the
local endpoint is marked dead.
Only after destroying the connections can we close the socket lest we get
an oops in a workqueue that's looking at a connection or a peer.
Fixes: 3d18cbb7fd0c ("rxrpc: Fix conn expiry timers")
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
---
net/rxrpc/af_rxrpc.c | 3 ---
net/rxrpc/ar-internal.h | 1 +
net/rxrpc/conn_client.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
net/rxrpc/conn_object.c | 2 +-
net/rxrpc/local_object.c | 5 ++++-
5 files changed, 55 insertions(+), 5 deletions(-)
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index 0dbbfd1b6487..d72ddb67bb74 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -862,7 +862,6 @@ static void rxrpc_sock_destructor(struct sock *sk)
static int rxrpc_release_sock(struct sock *sk)
{
struct rxrpc_sock *rx = rxrpc_sk(sk);
- struct rxrpc_net *rxnet = rxrpc_net(sock_net(&rx->sk));
_enter("%p{%d,%d}", sk, sk->sk_state, refcount_read(&sk->sk_refcnt));
@@ -898,8 +897,6 @@ static int rxrpc_release_sock(struct sock *sk)
rxrpc_release_calls_on_socket(rx);
flush_workqueue(rxrpc_workqueue);
rxrpc_purge_queue(&sk->sk_receive_queue);
- rxrpc_queue_work(&rxnet->service_conn_reaper);
- rxrpc_queue_work(&rxnet->client_conn_reaper);
rxrpc_unuse_local(rx->local);
rx->local = NULL;
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index a42d6b833675..ef5aa28e679c 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -911,6 +911,7 @@ void rxrpc_disconnect_client_call(struct rxrpc_call *);
void rxrpc_put_client_conn(struct rxrpc_connection *);
void rxrpc_discard_expired_client_conns(struct work_struct *);
void rxrpc_destroy_all_client_connections(struct rxrpc_net *);
+void rxrpc_clean_up_local_conns(struct rxrpc_local *);
/*
* conn_event.c
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index aea82f909c60..2244fb7f53ec 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -1162,3 +1162,52 @@ void rxrpc_destroy_all_client_connections(struct rxrpc_net *rxnet)
_leave("");
}
+
+/*
+ * Clean up the client connections on a local endpoint.
+ */
+void rxrpc_clean_up_local_conns(struct rxrpc_local *local)
+{
+ struct rxrpc_connection *conn, *tmp;
+ struct rxrpc_net *rxnet = local->rxnet;
+ unsigned int nr_active;
+ LIST_HEAD(graveyard);
+
+ _enter("");
+
+ spin_lock(&rxnet->client_conn_cache_lock);
+ nr_active = rxnet->nr_active_client_conns;
+
+ list_for_each_entry_safe(conn, tmp, &rxnet->idle_client_conns,
+ cache_link) {
+ if (conn->params.local == local) {
+ ASSERTCMP(conn->cache_state, ==, RXRPC_CONN_CLIENT_IDLE);
+
+ trace_rxrpc_client(conn, -1, rxrpc_client_discard);
+ if (!test_and_clear_bit(RXRPC_CONN_EXPOSED, &conn->flags))
+ BUG();
+ conn->cache_state = RXRPC_CONN_CLIENT_INACTIVE;
+ list_move(&conn->cache_link, &graveyard);
+ nr_active--;
+ }
+ }
+
+ rxnet->nr_active_client_conns = nr_active;
+ spin_unlock(&rxnet->client_conn_cache_lock);
+ ASSERTCMP(nr_active, >=, 0);
+
+ spin_lock(&rxnet->client_conn_cache_lock);
+ while (!list_empty(&graveyard)) {
+ conn = list_entry(graveyard.next,
+ struct rxrpc_connection, cache_link);
+ list_del_init(&conn->cache_link);
+ spin_unlock(&rxnet->client_conn_cache_lock);
+
+ rxrpc_put_connection(conn);
+
+ spin_lock(&rxnet->client_conn_cache_lock);
+ }
+ spin_unlock(&rxnet->client_conn_cache_lock);
+
+ _leave(" [culled]");
+}
diff --git a/net/rxrpc/conn_object.c b/net/rxrpc/conn_object.c
index 434ef392212b..ed05b6922132 100644
--- a/net/rxrpc/conn_object.c
+++ b/net/rxrpc/conn_object.c
@@ -398,7 +398,7 @@ void rxrpc_service_connection_reaper(struct work_struct *work)
if (conn->state == RXRPC_CONN_SERVICE_PREALLOC)
continue;
- if (rxnet->live) {
+ if (rxnet->live && !conn->params.local->dead) {
idle_timestamp = READ_ONCE(conn->idle_timestamp);
expire_at = idle_timestamp + rxrpc_connection_expiry * HZ;
if (conn->params.local->service_closed)
diff --git a/net/rxrpc/local_object.c b/net/rxrpc/local_object.c
index 72a6e12a9304..36587260cabd 100644
--- a/net/rxrpc/local_object.c
+++ b/net/rxrpc/local_object.c
@@ -426,11 +426,14 @@ static void rxrpc_local_destroyer(struct rxrpc_local *local)
_enter("%d", local->debug_id);
+ local->dead = true;
+
mutex_lock(&rxnet->local_mutex);
list_del_init(&local->link);
mutex_unlock(&rxnet->local_mutex);
- ASSERT(RB_EMPTY_ROOT(&local->client_conns));
+ rxrpc_clean_up_local_conns(local);
+ rxrpc_service_connection_reaper(&rxnet->service_conn_reaper);
ASSERT(!local->service);
if (socket) {
^ permalink raw reply related
* Re: [PATCH net 0/9] rxrpc: Fix use of skb_cow_data()
From: David Howells @ 2019-08-22 12:25 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647655350.10908.12081183247715153431.stgit@warthog.procyon.org.uk>
Sorry, I forgot to add a tested-by. Will resend.
David
^ permalink raw reply
* [PATCH net 9/9] rxrpc: Only call skb_cow_data() once per packet
From: David Howells @ 2019-08-22 12:24 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Move the call of skb_cow_data() from rxkad into rxrpc_recvmsg_data() and do
it as soon as the packet is first seen. This means that we only call this
function once per packet, even for a jumbo packet with a bunch of
subpackets.
In rxkad, we then have to guess how large a scatter-gather table we need
for decryption, particularly in rxkad_verify_packet_2(). We do this either
by creating an sg table that should be large enough, or by looking at
nr_frags on the skb.
Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/ar-internal.h | 1 +
net/rxrpc/input.c | 1 +
net/rxrpc/recvmsg.c | 11 ++++++++++-
net/rxrpc/rxkad.c | 32 +++++++++-----------------------
4 files changed, 21 insertions(+), 24 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index d784d58e0a0d..a42d6b833675 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -190,6 +190,7 @@ struct rxrpc_skb_priv {
u8 rx_flags; /* Received packet flags */
#define RXRPC_SKB_INCL_LAST 0x01 /* - Includes last packet */
#define RXRPC_SKB_TX_BUFFER 0x02 /* - Is transmit buffer */
+#define RXRPC_SKB_NEEDS_COW 0x04 /* - Needs skb_cow_data() calling */
union {
int remain; /* amount of space remaining for next write */
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 660b7eed39b7..4df39f391e9d 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -448,6 +448,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
}
atomic_set(&sp->nr_ring_pins, 1);
+ sp->rx_flags |= RXRPC_SKB_NEEDS_COW;
if (call->state == RXRPC_CALL_SERVER_RECV_REQUEST) {
unsigned long timo = READ_ONCE(call->next_req_timo);
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 82bb48d96526..ef50580b5295 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -305,7 +305,7 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
size_t len, int flags, size_t *_offset)
{
struct rxrpc_skb_priv *sp;
- struct sk_buff *skb;
+ struct sk_buff *skb, *trailer;
rxrpc_serial_t serial;
rxrpc_seq_t hard_ack, top, seq;
size_t remain;
@@ -343,6 +343,15 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
rxrpc_see_skb(skb, rxrpc_skb_seen);
sp = rxrpc_skb(skb);
+ if (sp->rx_flags & RXRPC_SKB_NEEDS_COW) {
+ ret2 = skb_cow_data(skb, 0, &trailer);
+ if (ret2 < 0) {
+ ret = ret2;
+ goto out;
+ }
+ sp->rx_flags &= ~RXRPC_SKB_NEEDS_COW;
+ }
+
if (!(flags & MSG_PEEK)) {
serial = sp->hdr.serial;
serial += call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET;
diff --git a/net/rxrpc/rxkad.c b/net/rxrpc/rxkad.c
index ae8cd8926456..c60c520fde7c 100644
--- a/net/rxrpc/rxkad.c
+++ b/net/rxrpc/rxkad.c
@@ -187,10 +187,8 @@ static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call,
struct rxrpc_skb_priv *sp;
struct rxrpc_crypt iv;
struct scatterlist sg[16];
- struct sk_buff *trailer;
unsigned int len;
u16 check;
- int nsg;
int err;
sp = rxrpc_skb(skb);
@@ -214,15 +212,14 @@ static int rxkad_secure_packet_encrypt(const struct rxrpc_call *call,
crypto_skcipher_encrypt(req);
/* we want to encrypt the skbuff in-place */
- nsg = skb_cow_data(skb, 0, &trailer);
- err = -ENOMEM;
- if (nsg < 0 || nsg > 16)
+ err = -EMSGSIZE;
+ if (skb_shinfo(skb)->nr_frags > 16)
goto out;
len = data_size + call->conn->size_align - 1;
len &= ~(call->conn->size_align - 1);
- sg_init_table(sg, nsg);
+ sg_init_table(sg, ARRAY_SIZE(sg));
err = skb_to_sgvec(skb, sg, 0, len);
if (unlikely(err < 0))
goto out;
@@ -319,11 +316,10 @@ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb,
struct rxkad_level1_hdr sechdr;
struct rxrpc_crypt iv;
struct scatterlist sg[16];
- struct sk_buff *trailer;
bool aborted;
u32 data_size, buf;
u16 check;
- int nsg, ret;
+ int ret;
_enter("");
@@ -336,11 +332,7 @@ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb,
/* Decrypt the skbuff in-place. TODO: We really want to decrypt
* directly into the target buffer.
*/
- nsg = skb_cow_data(skb, 0, &trailer);
- if (nsg < 0 || nsg > 16)
- goto nomem;
-
- sg_init_table(sg, nsg);
+ sg_init_table(sg, ARRAY_SIZE(sg));
ret = skb_to_sgvec(skb, sg, offset, 8);
if (unlikely(ret < 0))
return ret;
@@ -388,10 +380,6 @@ static int rxkad_verify_packet_1(struct rxrpc_call *call, struct sk_buff *skb,
if (aborted)
rxrpc_send_abort_packet(call);
return -EPROTO;
-
-nomem:
- _leave(" = -ENOMEM");
- return -ENOMEM;
}
/*
@@ -406,7 +394,6 @@ static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb,
struct rxkad_level2_hdr sechdr;
struct rxrpc_crypt iv;
struct scatterlist _sg[4], *sg;
- struct sk_buff *trailer;
bool aborted;
u32 data_size, buf;
u16 check;
@@ -423,12 +410,11 @@ static int rxkad_verify_packet_2(struct rxrpc_call *call, struct sk_buff *skb,
/* Decrypt the skbuff in-place. TODO: We really want to decrypt
* directly into the target buffer.
*/
- nsg = skb_cow_data(skb, 0, &trailer);
- if (nsg < 0)
- goto nomem;
-
sg = _sg;
- if (unlikely(nsg > 4)) {
+ nsg = skb_shinfo(skb)->nr_frags;
+ if (nsg <= 4) {
+ nsg = 4;
+ } else {
sg = kmalloc_array(nsg, sizeof(*sg), GFP_NOIO);
if (!sg)
goto nomem;
^ permalink raw reply related
* [PATCH net 8/9] rxrpc: Use shadow refcount for packets in the RxTx ring
From: David Howells @ 2019-08-22 12:24 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Use the previously added shadow refcount for packets that are in the Rx/Tx
ring so that the ring itself only ever holds a single ref on the skbuff.
This allows skb_cow_data() to be used by the recvmsg code to make the data
modifyable for in-place decryption without triggering the assertion in
pskb_expand_head:
BUG_ON(skb_shared(skb));
This *should* be okay as:
(1) Once rxrpc_input_data() starts attaching the sk_buff to the ring, it
no longer looks inside the packet (all the parsing was done previously
and notes were taken in struct rxrpc_skb_priv).
(2) rxrpc_recvmsg_data() may not run in parallel for a particular call.
(3) rxrpc_recvmsg_data() cow's the sk_buff the first time it sees it and
then steps through each pointer from the buffer in order, unpinning as
it goes.
Each subpacket is individually and sequentially decrypted in place in
the sk_buff, hence the need for skb_cow_data().
(4) No one else can be looking in a packet in the Rx ring once it's there.
The problem was occuring because the softirq handler may be holding a ref
or the ring may be holding multiple refs when skb_cow_data() is called in
rxkad_verify_packet(), and so skb_shared() returns true and
__pskb_pull_tail() dislikes that. If this occurs, something like the
following report will be generated.
kernel BUG at net/core/skbuff.c:1463!
...
RIP: 0010:pskb_expand_head+0x253/0x2b0
...
Call Trace:
__pskb_pull_tail+0x49/0x460
skb_cow_data+0x6f/0x300
rxkad_verify_packet+0x18b/0xb10 [rxrpc]
rxrpc_recvmsg_data.isra.11+0x4a8/0xa10 [rxrpc]
rxrpc_kernel_recv_data+0x126/0x240 [rxrpc]
afs_extract_data+0x51/0x2d0 [kafs]
afs_deliver_fs_fetch_data+0x188/0x400 [kafs]
afs_deliver_to_call+0xac/0x430 [kafs]
afs_wait_for_call_to_complete+0x22f/0x3d0 [kafs]
afs_make_call+0x282/0x3f0 [kafs]
afs_fs_fetch_data+0x164/0x300 [kafs]
afs_fetch_data+0x54/0x130 [kafs]
afs_readpages+0x20d/0x340 [kafs]
read_pages+0x66/0x180
__do_page_cache_readahead+0x188/0x1a0
ondemand_readahead+0x17d/0x2e0
generic_file_read_iter+0x740/0xc10
__vfs_read+0x145/0x1a0
vfs_read+0x8c/0x140
ksys_read+0x4a/0xb0
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Reported-by: Julian Wollrath <jwollrath@web.de>
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/call_object.c | 2 +-
net/rxrpc/input.c | 22 ++++++++++------------
net/rxrpc/recvmsg.c | 2 +-
net/rxrpc/sendmsg.c | 1 +
4 files changed, 13 insertions(+), 14 deletions(-)
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 014548c259ce..830b6152dfa3 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -429,7 +429,7 @@ static void rxrpc_cleanup_ring(struct rxrpc_call *call)
int i;
for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
- rxrpc_free_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
+ rxrpc_unpin_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
call->rxtx_buffer[i] = NULL;
}
}
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 31090bdf1fae..660b7eed39b7 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -258,7 +258,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
skb = list;
list = skb->next;
skb_mark_not_on_list(skb);
- rxrpc_free_skb(skb, rxrpc_skb_freed);
+ rxrpc_unpin_skb(skb, rxrpc_skb_unpin);
}
return rot_last;
@@ -447,6 +447,8 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
return;
}
+ atomic_set(&sp->nr_ring_pins, 1);
+
if (call->state == RXRPC_CALL_SERVER_RECV_REQUEST) {
unsigned long timo = READ_ONCE(call->next_req_timo);
unsigned long now, expect_req_by;
@@ -550,6 +552,12 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
ack_serial = serial;
}
+ /* Each insertion into the rxtx_buffer holds a ring pin. This
+ * allows a single ref on the buffer to be shared, thereby
+ * allowing skb_cow_data() to be used.
+ */
+ rxrpc_pin_skb(skb, rxrpc_skb_pin);
+
/* Queue the packet. We use a couple of memory barriers here as need
* to make sure that rx_top is perceived to be set after the buffer
* pointer and that the buffer pointer is set after the annotation and
@@ -558,8 +566,6 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
* Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
* and also rxrpc_fill_out_ack().
*/
- if (!terminal)
- rxrpc_get_skb(skb, rxrpc_skb_got);
call->rxtx_annotations[ix] = annotation;
smp_wmb();
call->rxtx_buffer[ix] = skb;
@@ -574,14 +580,6 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
immediate_ack = true;
}
- if (terminal) {
- /* From this point on, we're not allowed to touch the
- * packet any longer as its ref now belongs to the Rx
- * ring.
- */
- skb = NULL;
- }
-
if (last) {
set_bit(RXRPC_CALL_RX_LAST, &call->flags);
if (!ack) {
@@ -620,7 +618,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
unlock:
spin_unlock(&call->input_lock);
- rxrpc_free_skb(skb, rxrpc_skb_freed);
+ rxrpc_unpin_skb(skb, rxrpc_skb_unpin);
_leave(" [queued]");
}
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 3b0becb12041..82bb48d96526 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -205,7 +205,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
/* Barrier against rxrpc_input_data(). */
smp_store_release(&call->rx_hard_ack, hard_ack);
- rxrpc_free_skb(skb, rxrpc_skb_freed);
+ rxrpc_unpin_skb(skb, rxrpc_skb_unpin);
trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack);
if (last) {
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 6a1547b270fe..ba0e2aa268b1 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -175,6 +175,7 @@ static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
*/
skb->tstamp = ktime_get_real();
+ atomic_set(&sp->nr_ring_pins, 1);
ix = seq & RXRPC_RXTX_BUFF_MASK;
rxrpc_get_skb(skb, rxrpc_skb_got);
call->rxtx_annotations[ix] = annotation;
^ permalink raw reply related
* [PATCH net 7/9] rxrpc: Add a shadow refcount in the skb private data
From: David Howells @ 2019-08-22 12:24 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Add a shadow refcount to count pins from the Rx/Tx ring on an sk_buff so
that we can hold multiple refs on it without causing skb_cow_data() to
throw an assertion.
This is stored in the private part of the sk_buff as laid out in struct
rxrpc_skb_priv.
Add two accessor functions for pinning (adding) or unpinning (discarding) a
shadow ref.
Signed-off-by: David Howells <dhowells@redhat.com>
---
include/trace/events/rxrpc.h | 15 ++++++++---
net/rxrpc/ar-internal.h | 2 +
net/rxrpc/skbuff.c | 57 ++++++++++++++++++++++++++++++++++++++----
3 files changed, 65 insertions(+), 9 deletions(-)
diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index e2356c51883b..34237ea8ceb0 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -28,10 +28,12 @@ enum rxrpc_skb_trace {
rxrpc_skb_got,
rxrpc_skb_lost,
rxrpc_skb_new,
+ rxrpc_skb_pin,
rxrpc_skb_purged,
rxrpc_skb_received,
rxrpc_skb_rotated,
rxrpc_skb_seen,
+ rxrpc_skb_unpin,
};
enum rxrpc_local_trace {
@@ -228,10 +230,12 @@ enum rxrpc_tx_point {
EM(rxrpc_skb_got, "GOT") \
EM(rxrpc_skb_lost, "*L*") \
EM(rxrpc_skb_new, "NEW") \
+ EM(rxrpc_skb_pin, "PIN") \
EM(rxrpc_skb_purged, "PUR") \
EM(rxrpc_skb_received, "RCV") \
EM(rxrpc_skb_rotated, "ROT") \
- E_(rxrpc_skb_seen, "SEE")
+ EM(rxrpc_skb_seen, "SEE") \
+ E_(rxrpc_skb_unpin, "UPN")
#define rxrpc_local_traces \
EM(rxrpc_local_got, "GOT") \
@@ -633,14 +637,15 @@ TRACE_EVENT(rxrpc_call,
TRACE_EVENT(rxrpc_skb,
TP_PROTO(struct sk_buff *skb, enum rxrpc_skb_trace op,
- int usage, int mod_count, const void *where),
+ int usage, int mod_count, int pins, const void *where),
- TP_ARGS(skb, op, usage, mod_count, where),
+ TP_ARGS(skb, op, usage, mod_count, pins, where),
TP_STRUCT__entry(
__field(struct sk_buff *, skb )
__field(enum rxrpc_skb_trace, op )
__field(u8, flags )
+ __field(u8, pins )
__field(int, usage )
__field(int, mod_count )
__field(const void *, where )
@@ -651,16 +656,18 @@ TRACE_EVENT(rxrpc_skb,
__entry->flags = rxrpc_skb(skb)->rx_flags;
__entry->op = op;
__entry->usage = usage;
+ __entry->pins = pins;
__entry->mod_count = mod_count;
__entry->where = where;
),
- TP_printk("s=%p %cx %s u=%d m=%d p=%pSR",
+ TP_printk("s=%p %cx %s u=%d m=%d r=%u p=%pSR",
__entry->skb,
__entry->flags & RXRPC_SKB_TX_BUFFER ? 'T' : 'R',
__print_symbolic(__entry->op, rxrpc_skb_traces),
__entry->usage,
__entry->mod_count,
+ __entry->pins,
__entry->where)
);
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 2d5294f3e62f..d784d58e0a0d 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -1113,6 +1113,8 @@ void rxrpc_see_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_get_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_free_skb(struct sk_buff *, enum rxrpc_skb_trace);
void rxrpc_purge_queue(struct sk_buff_head *);
+void rxrpc_pin_skb(struct sk_buff *, enum rxrpc_skb_trace);
+void rxrpc_unpin_skb(struct sk_buff *, enum rxrpc_skb_trace);
/*
* sysctl.c
diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c
index 8e6f45f84b9b..f9986a1510d3 100644
--- a/net/rxrpc/skbuff.c
+++ b/net/rxrpc/skbuff.c
@@ -22,9 +22,12 @@
*/
void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
const void *here = __builtin_return_address(0);
int n = atomic_inc_return(select_skb_count(skb));
- trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
+
+ atomic_set(&sp->nr_ring_pins, 1);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, 1, here);
}
/*
@@ -33,9 +36,12 @@ void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
+
if (skb) {
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
int n = atomic_read(select_skb_count(skb));
- trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n,
+ atomic_read(&sp->nr_ring_pins), here);
}
}
@@ -44,9 +50,11 @@ void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
*/
void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
const void *here = __builtin_return_address(0);
int n = atomic_inc_return(select_skb_count(skb));
- trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n,
+ atomic_read(&sp->nr_ring_pins), here);
skb_get(skb);
}
@@ -56,11 +64,14 @@ void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
+
if (skb) {
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
int n;
CHECK_SLAB_OKAY(&skb->users);
n = atomic_dec_return(select_skb_count(skb));
- trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n,
+ atomic_read(&sp->nr_ring_pins), here);
kfree_skb(skb);
}
}
@@ -72,10 +83,46 @@ void rxrpc_purge_queue(struct sk_buff_head *list)
{
const void *here = __builtin_return_address(0);
struct sk_buff *skb;
+
while ((skb = skb_dequeue((list))) != NULL) {
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
int n = atomic_dec_return(select_skb_count(skb));
trace_rxrpc_skb(skb, rxrpc_skb_purged,
- refcount_read(&skb->users), n, here);
+ refcount_read(&skb->users), n,
+ atomic_read(&sp->nr_ring_pins), here);
kfree_skb(skb);
}
}
+
+/*
+ * Add a secondary ref on the socket buffer.
+ */
+void rxrpc_pin_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
+{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ const void *here = __builtin_return_address(0);
+ int n = atomic_read(select_skb_count(skb));
+ int np;
+
+ np = atomic_inc_return(&sp->nr_ring_pins);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, np, here);
+}
+
+/*
+ * Remove a secondary ref on the socket buffer.
+ */
+void rxrpc_unpin_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
+{
+ const void *here = __builtin_return_address(0);
+
+ if (skb) {
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
+ int n = atomic_read(select_skb_count(skb));
+ int np;
+
+ np = atomic_dec_return(&sp->nr_ring_pins);
+ trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, np, here);
+ if (np == 0)
+ rxrpc_free_skb(skb, op);
+ }
+}
^ permalink raw reply related
* [PATCH net 6/9] rxrpc: Use the tx-phase skb flag to simplify tracing
From: David Howells @ 2019-08-22 12:24 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Use the previously-added transmit-phase skbuff private flag to simplify the
socket buffer tracing a bit. Which phase the skbuff comes from can now be
divined from the skb rather than having to be guessed from the call state.
We can also reduce the number of rxrpc_skb_trace values by eliminating the
difference between Tx and Rx in the symbols.
Signed-off-by: David Howells <dhowells@redhat.com>
---
include/trace/events/rxrpc.h | 51 ++++++++++++++++++------------------------
net/rxrpc/ar-internal.h | 1 +
net/rxrpc/call_event.c | 8 +++----
net/rxrpc/call_object.c | 6 ++---
net/rxrpc/conn_event.c | 6 ++---
net/rxrpc/input.c | 22 +++++++++---------
net/rxrpc/local_event.c | 4 ++-
net/rxrpc/output.c | 6 ++---
net/rxrpc/peer_event.c | 10 ++++----
net/rxrpc/recvmsg.c | 6 ++---
net/rxrpc/sendmsg.c | 10 ++++----
net/rxrpc/skbuff.c | 15 +++++++-----
12 files changed, 69 insertions(+), 76 deletions(-)
diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index fa06b528c73c..e2356c51883b 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -23,20 +23,15 @@
#define __RXRPC_DECLARE_TRACE_ENUMS_ONCE_ONLY
enum rxrpc_skb_trace {
- rxrpc_skb_rx_cleaned,
- rxrpc_skb_rx_freed,
- rxrpc_skb_rx_got,
- rxrpc_skb_rx_lost,
- rxrpc_skb_rx_purged,
- rxrpc_skb_rx_received,
- rxrpc_skb_rx_rotated,
- rxrpc_skb_rx_seen,
- rxrpc_skb_tx_cleaned,
- rxrpc_skb_tx_freed,
- rxrpc_skb_tx_got,
- rxrpc_skb_tx_new,
- rxrpc_skb_tx_rotated,
- rxrpc_skb_tx_seen,
+ rxrpc_skb_cleaned,
+ rxrpc_skb_freed,
+ rxrpc_skb_got,
+ rxrpc_skb_lost,
+ rxrpc_skb_new,
+ rxrpc_skb_purged,
+ rxrpc_skb_received,
+ rxrpc_skb_rotated,
+ rxrpc_skb_seen,
};
enum rxrpc_local_trace {
@@ -228,20 +223,15 @@ enum rxrpc_tx_point {
* Declare tracing information enums and their string mappings for display.
*/
#define rxrpc_skb_traces \
- EM(rxrpc_skb_rx_cleaned, "Rx CLN") \
- EM(rxrpc_skb_rx_freed, "Rx FRE") \
- EM(rxrpc_skb_rx_got, "Rx GOT") \
- EM(rxrpc_skb_rx_lost, "Rx *L*") \
- EM(rxrpc_skb_rx_purged, "Rx PUR") \
- EM(rxrpc_skb_rx_received, "Rx RCV") \
- EM(rxrpc_skb_rx_rotated, "Rx ROT") \
- EM(rxrpc_skb_rx_seen, "Rx SEE") \
- EM(rxrpc_skb_tx_cleaned, "Tx CLN") \
- EM(rxrpc_skb_tx_freed, "Tx FRE") \
- EM(rxrpc_skb_tx_got, "Tx GOT") \
- EM(rxrpc_skb_tx_new, "Tx NEW") \
- EM(rxrpc_skb_tx_rotated, "Tx ROT") \
- E_(rxrpc_skb_tx_seen, "Tx SEE")
+ EM(rxrpc_skb_cleaned, "CLN") \
+ EM(rxrpc_skb_freed, "FRE") \
+ EM(rxrpc_skb_got, "GOT") \
+ EM(rxrpc_skb_lost, "*L*") \
+ EM(rxrpc_skb_new, "NEW") \
+ EM(rxrpc_skb_purged, "PUR") \
+ EM(rxrpc_skb_received, "RCV") \
+ EM(rxrpc_skb_rotated, "ROT") \
+ E_(rxrpc_skb_seen, "SEE")
#define rxrpc_local_traces \
EM(rxrpc_local_got, "GOT") \
@@ -650,6 +640,7 @@ TRACE_EVENT(rxrpc_skb,
TP_STRUCT__entry(
__field(struct sk_buff *, skb )
__field(enum rxrpc_skb_trace, op )
+ __field(u8, flags )
__field(int, usage )
__field(int, mod_count )
__field(const void *, where )
@@ -657,14 +648,16 @@ TRACE_EVENT(rxrpc_skb,
TP_fast_assign(
__entry->skb = skb;
+ __entry->flags = rxrpc_skb(skb)->rx_flags;
__entry->op = op;
__entry->usage = usage;
__entry->mod_count = mod_count;
__entry->where = where;
),
- TP_printk("s=%p %s u=%d m=%d p=%pSR",
+ TP_printk("s=%p %cx %s u=%d m=%d p=%pSR",
__entry->skb,
+ __entry->flags & RXRPC_SKB_TX_BUFFER ? 'T' : 'R',
__print_symbolic(__entry->op, rxrpc_skb_traces),
__entry->usage,
__entry->mod_count,
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 63d3a91ce5e9..2d5294f3e62f 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -185,6 +185,7 @@ struct rxrpc_host_header {
* - max 48 bytes (struct sk_buff::cb)
*/
struct rxrpc_skb_priv {
+ atomic_t nr_ring_pins; /* Number of rxtx ring pins */
u8 nr_subpackets; /* Number of subpackets */
u8 rx_flags; /* Received packet flags */
#define RXRPC_SKB_INCL_LAST 0x01 /* - Includes last packet */
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index c767679bfa5d..cedbbb3a7c2e 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -199,7 +199,7 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j)
continue;
skb = call->rxtx_buffer[ix];
- rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
if (anno_type == RXRPC_TX_ANNO_UNACK) {
if (ktime_after(skb->tstamp, max_age)) {
@@ -255,18 +255,18 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j)
continue;
skb = call->rxtx_buffer[ix];
- rxrpc_get_skb(skb, rxrpc_skb_tx_got);
+ rxrpc_get_skb(skb, rxrpc_skb_got);
spin_unlock_bh(&call->lock);
if (rxrpc_send_data_packet(call, skb, true) < 0) {
- rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
return;
}
if (rxrpc_is_client_call(call))
rxrpc_expose_client_call(call);
- rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
spin_lock_bh(&call->lock);
/* We need to clear the retransmit state, but there are two
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index c9ab2da957fe..014548c259ce 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -429,9 +429,7 @@ static void rxrpc_cleanup_ring(struct rxrpc_call *call)
int i;
for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
- rxrpc_free_skb(call->rxtx_buffer[i],
- (call->tx_phase ? rxrpc_skb_tx_cleaned :
- rxrpc_skb_rx_cleaned));
+ rxrpc_free_skb(call->rxtx_buffer[i], rxrpc_skb_cleaned);
call->rxtx_buffer[i] = NULL;
}
}
@@ -587,7 +585,7 @@ void rxrpc_cleanup_call(struct rxrpc_call *call)
ASSERTCMP(call->conn, ==, NULL);
rxrpc_cleanup_ring(call);
- rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
+ rxrpc_free_skb(call->tx_pending, rxrpc_skb_cleaned);
call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
}
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index df6624c140be..a1ceef4f5cd0 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -472,7 +472,7 @@ void rxrpc_process_connection(struct work_struct *work)
/* go through the conn-level event packets, releasing the ref on this
* connection that each one has when we've finished with it */
while ((skb = skb_dequeue(&conn->rx_queue))) {
- rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
ret = rxrpc_process_event(conn, skb, &abort_code);
switch (ret) {
case -EPROTO:
@@ -484,7 +484,7 @@ void rxrpc_process_connection(struct work_struct *work)
goto requeue_and_leave;
case -ECONNABORTED:
default:
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
break;
}
}
@@ -501,6 +501,6 @@ void rxrpc_process_connection(struct work_struct *work)
protocol_error:
if (rxrpc_abort_connection(conn, ret, abort_code) < 0)
goto requeue_and_leave;
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
goto out;
}
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 140cede77655..31090bdf1fae 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -233,7 +233,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
ix = call->tx_hard_ack & RXRPC_RXTX_BUFF_MASK;
skb = call->rxtx_buffer[ix];
annotation = call->rxtx_annotations[ix];
- rxrpc_see_skb(skb, rxrpc_skb_tx_rotated);
+ rxrpc_see_skb(skb, rxrpc_skb_rotated);
call->rxtx_buffer[ix] = NULL;
call->rxtx_annotations[ix] = 0;
skb->next = list;
@@ -258,7 +258,7 @@ static bool rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
skb = list;
list = skb->next;
skb_mark_not_on_list(skb);
- rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
}
return rot_last;
@@ -443,7 +443,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
state = READ_ONCE(call->state);
if (state >= RXRPC_CALL_COMPLETE) {
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
return;
}
@@ -559,7 +559,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
* and also rxrpc_fill_out_ack().
*/
if (!terminal)
- rxrpc_get_skb(skb, rxrpc_skb_rx_got);
+ rxrpc_get_skb(skb, rxrpc_skb_got);
call->rxtx_annotations[ix] = annotation;
smp_wmb();
call->rxtx_buffer[ix] = skb;
@@ -620,7 +620,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
unlock:
spin_unlock(&call->input_lock);
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
_leave(" [queued]");
}
@@ -1056,7 +1056,7 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call,
break;
}
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
no_free:
_leave("");
}
@@ -1119,7 +1119,7 @@ static void rxrpc_post_packet_to_local(struct rxrpc_local *local,
skb_queue_tail(&local->event_queue, skb);
rxrpc_queue_local(local);
} else {
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
}
}
@@ -1134,7 +1134,7 @@ static void rxrpc_reject_packet(struct rxrpc_local *local, struct sk_buff *skb)
skb_queue_tail(&local->reject_queue, skb);
rxrpc_queue_local(local);
} else {
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
}
}
@@ -1198,7 +1198,7 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
if (skb->tstamp == 0)
skb->tstamp = ktime_get_real();
- rxrpc_new_skb(skb, rxrpc_skb_rx_received);
+ rxrpc_new_skb(skb, rxrpc_skb_received);
skb_pull(skb, sizeof(struct udphdr));
@@ -1215,7 +1215,7 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
static int lose;
if ((lose++ & 7) == 7) {
trace_rxrpc_rx_lose(sp);
- rxrpc_free_skb(skb, rxrpc_skb_rx_lost);
+ rxrpc_free_skb(skb, rxrpc_skb_lost);
return 0;
}
}
@@ -1389,7 +1389,7 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
goto out;
discard:
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
out:
trace_rxrpc_rx_done(0, 0);
return 0;
diff --git a/net/rxrpc/local_event.c b/net/rxrpc/local_event.c
index e93a78f7c05e..3ce6d628cd75 100644
--- a/net/rxrpc/local_event.c
+++ b/net/rxrpc/local_event.c
@@ -90,7 +90,7 @@ void rxrpc_process_local_events(struct rxrpc_local *local)
if (skb) {
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
- rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
_debug("{%d},{%u}", local->debug_id, sp->hdr.type);
switch (sp->hdr.type) {
@@ -108,7 +108,7 @@ void rxrpc_process_local_events(struct rxrpc_local *local)
break;
}
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
}
_leave("");
diff --git a/net/rxrpc/output.c b/net/rxrpc/output.c
index 369e516c4bdf..935bb60fff56 100644
--- a/net/rxrpc/output.c
+++ b/net/rxrpc/output.c
@@ -565,7 +565,7 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
memset(&whdr, 0, sizeof(whdr));
while ((skb = skb_dequeue(&local->reject_queue))) {
- rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
sp = rxrpc_skb(skb);
switch (skb->mark) {
@@ -581,7 +581,7 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
ioc = 2;
break;
default:
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
continue;
}
@@ -606,7 +606,7 @@ void rxrpc_reject_packets(struct rxrpc_local *local)
rxrpc_tx_point_reject);
}
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
}
_leave("");
diff --git a/net/rxrpc/peer_event.c b/net/rxrpc/peer_event.c
index 7666ec72d37e..c97ebdc043e4 100644
--- a/net/rxrpc/peer_event.c
+++ b/net/rxrpc/peer_event.c
@@ -163,11 +163,11 @@ void rxrpc_error_report(struct sock *sk)
_leave("UDP socket errqueue empty");
return;
}
- rxrpc_new_skb(skb, rxrpc_skb_rx_received);
+ rxrpc_new_skb(skb, rxrpc_skb_received);
serr = SKB_EXT_ERR(skb);
if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) {
_leave("UDP empty message");
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
return;
}
@@ -177,7 +177,7 @@ void rxrpc_error_report(struct sock *sk)
peer = NULL;
if (!peer) {
rcu_read_unlock();
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
_leave(" [no peer]");
return;
}
@@ -189,7 +189,7 @@ void rxrpc_error_report(struct sock *sk)
serr->ee.ee_code == ICMP_FRAG_NEEDED)) {
rxrpc_adjust_mtu(peer, serr);
rcu_read_unlock();
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
rxrpc_put_peer(peer);
_leave(" [MTU update]");
return;
@@ -197,7 +197,7 @@ void rxrpc_error_report(struct sock *sk)
rxrpc_store_error(peer, serr);
rcu_read_unlock();
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
rxrpc_put_peer(peer);
_leave("");
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index e49eacfaf4d6..3b0becb12041 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -190,7 +190,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
hard_ack++;
ix = hard_ack & RXRPC_RXTX_BUFF_MASK;
skb = call->rxtx_buffer[ix];
- rxrpc_see_skb(skb, rxrpc_skb_rx_rotated);
+ rxrpc_see_skb(skb, rxrpc_skb_rotated);
sp = rxrpc_skb(skb);
subpacket = call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET;
@@ -205,7 +205,7 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
/* Barrier against rxrpc_input_data(). */
smp_store_release(&call->rx_hard_ack, hard_ack);
- rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack);
if (last) {
@@ -340,7 +340,7 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
break;
}
smp_rmb();
- rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
sp = rxrpc_skb(skb);
if (!(flags & MSG_PEEK)) {
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 472dc3b7d91f..6a1547b270fe 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -176,7 +176,7 @@ static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
skb->tstamp = ktime_get_real();
ix = seq & RXRPC_RXTX_BUFF_MASK;
- rxrpc_get_skb(skb, rxrpc_skb_tx_got);
+ rxrpc_get_skb(skb, rxrpc_skb_got);
call->rxtx_annotations[ix] = annotation;
smp_wmb();
call->rxtx_buffer[ix] = skb;
@@ -248,7 +248,7 @@ static int rxrpc_queue_packet(struct rxrpc_sock *rx, struct rxrpc_call *call,
}
out:
- rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
_leave(" = %d", ret);
return ret;
}
@@ -289,7 +289,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
skb = call->tx_pending;
call->tx_pending = NULL;
- rxrpc_see_skb(skb, rxrpc_skb_tx_seen);
+ rxrpc_see_skb(skb, rxrpc_skb_seen);
copied = 0;
do {
@@ -338,7 +338,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
sp = rxrpc_skb(skb);
sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
- rxrpc_new_skb(skb, rxrpc_skb_tx_new);
+ rxrpc_new_skb(skb, rxrpc_skb_new);
_debug("ALLOC SEND %p", skb);
@@ -440,7 +440,7 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
return ret;
call_terminated:
- rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
+ rxrpc_free_skb(skb, rxrpc_skb_freed);
_leave(" = %d", call->error);
return call->error;
diff --git a/net/rxrpc/skbuff.c b/net/rxrpc/skbuff.c
index 9ad5045b7c2f..8e6f45f84b9b 100644
--- a/net/rxrpc/skbuff.c
+++ b/net/rxrpc/skbuff.c
@@ -14,7 +14,8 @@
#include <net/af_rxrpc.h>
#include "ar-internal.h"
-#define select_skb_count(op) (op >= rxrpc_skb_tx_cleaned ? &rxrpc_n_tx_skbs : &rxrpc_n_rx_skbs)
+#define is_tx_skb(skb) (rxrpc_skb(skb)->rx_flags & RXRPC_SKB_TX_BUFFER)
+#define select_skb_count(skb) (is_tx_skb(skb) ? &rxrpc_n_tx_skbs : &rxrpc_n_rx_skbs)
/*
* Note the allocation or reception of a socket buffer.
@@ -22,7 +23,7 @@
void rxrpc_new_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
- int n = atomic_inc_return(select_skb_count(op));
+ int n = atomic_inc_return(select_skb_count(skb));
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
}
@@ -33,7 +34,7 @@ void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
if (skb) {
- int n = atomic_read(select_skb_count(op));
+ int n = atomic_read(select_skb_count(skb));
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
}
}
@@ -44,7 +45,7 @@ void rxrpc_see_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
void rxrpc_get_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
{
const void *here = __builtin_return_address(0);
- int n = atomic_inc_return(select_skb_count(op));
+ int n = atomic_inc_return(select_skb_count(skb));
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
skb_get(skb);
}
@@ -58,7 +59,7 @@ void rxrpc_free_skb(struct sk_buff *skb, enum rxrpc_skb_trace op)
if (skb) {
int n;
CHECK_SLAB_OKAY(&skb->users);
- n = atomic_dec_return(select_skb_count(op));
+ n = atomic_dec_return(select_skb_count(skb));
trace_rxrpc_skb(skb, op, refcount_read(&skb->users), n, here);
kfree_skb(skb);
}
@@ -72,8 +73,8 @@ void rxrpc_purge_queue(struct sk_buff_head *list)
const void *here = __builtin_return_address(0);
struct sk_buff *skb;
while ((skb = skb_dequeue((list))) != NULL) {
- int n = atomic_dec_return(select_skb_count(rxrpc_skb_rx_purged));
- trace_rxrpc_skb(skb, rxrpc_skb_rx_purged,
+ int n = atomic_dec_return(select_skb_count(skb));
+ trace_rxrpc_skb(skb, rxrpc_skb_purged,
refcount_read(&skb->users), n, here);
kfree_skb(skb);
}
^ permalink raw reply related
* [PATCH net 5/9] rxrpc: Abstract out rxtx ring cleanup
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Abstract out rxtx ring cleanup into its own function from its two callers.
This makes it easier to apply the same changes to both.
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/call_object.c | 33 +++++++++++++++++----------------
1 file changed, 17 insertions(+), 16 deletions(-)
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index 217b12be9e08..c9ab2da957fe 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -421,6 +421,21 @@ void rxrpc_get_call(struct rxrpc_call *call, enum rxrpc_call_trace op)
trace_rxrpc_call(call, op, n, here, NULL);
}
+/*
+ * Clean up the RxTx skb ring.
+ */
+static void rxrpc_cleanup_ring(struct rxrpc_call *call)
+{
+ int i;
+
+ for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
+ rxrpc_free_skb(call->rxtx_buffer[i],
+ (call->tx_phase ? rxrpc_skb_tx_cleaned :
+ rxrpc_skb_rx_cleaned));
+ call->rxtx_buffer[i] = NULL;
+ }
+}
+
/*
* Detach a call from its owning socket.
*/
@@ -429,7 +444,6 @@ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
const void *here = __builtin_return_address(0);
struct rxrpc_connection *conn = call->conn;
bool put = false;
- int i;
_enter("{%d,%d}", call->debug_id, atomic_read(&call->usage));
@@ -479,13 +493,7 @@ void rxrpc_release_call(struct rxrpc_sock *rx, struct rxrpc_call *call)
if (conn)
rxrpc_disconnect_call(call);
- for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++) {
- rxrpc_free_skb(call->rxtx_buffer[i],
- (call->tx_phase ? rxrpc_skb_tx_cleaned :
- rxrpc_skb_rx_cleaned));
- call->rxtx_buffer[i] = NULL;
- }
-
+ rxrpc_cleanup_ring(call);
_leave("");
}
@@ -568,8 +576,6 @@ static void rxrpc_rcu_destroy_call(struct rcu_head *rcu)
*/
void rxrpc_cleanup_call(struct rxrpc_call *call)
{
- int i;
-
_net("DESTROY CALL %d", call->debug_id);
memset(&call->sock_node, 0xcd, sizeof(call->sock_node));
@@ -580,12 +586,7 @@ void rxrpc_cleanup_call(struct rxrpc_call *call)
ASSERT(test_bit(RXRPC_CALL_RELEASED, &call->flags));
ASSERTCMP(call->conn, ==, NULL);
- /* Clean up the Rx/Tx buffer */
- for (i = 0; i < RXRPC_RXTX_BUFF_SIZE; i++)
- rxrpc_free_skb(call->rxtx_buffer[i],
- (call->tx_phase ? rxrpc_skb_tx_cleaned :
- rxrpc_skb_rx_cleaned));
-
+ rxrpc_cleanup_ring(call);
rxrpc_free_skb(call->tx_pending, rxrpc_skb_tx_cleaned);
call_rcu(&call->rcu, rxrpc_rcu_destroy_call);
^ permalink raw reply related
* [PATCH net 4/9] rxrpc: Add a private skb flag to indicate transmission-phase skbs
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Add a flag in the private data on an skbuff to indicate that this is a
transmission-phase buffer rather than a receive-phase buffer.
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/ar-internal.h | 1 +
net/rxrpc/sendmsg.c | 3 ++-
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 20d7907a5bc6..63d3a91ce5e9 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -188,6 +188,7 @@ struct rxrpc_skb_priv {
u8 nr_subpackets; /* Number of subpackets */
u8 rx_flags; /* Received packet flags */
#define RXRPC_SKB_INCL_LAST 0x01 /* - Includes last packet */
+#define RXRPC_SKB_TX_BUFFER 0x02 /* - Is transmit buffer */
union {
int remain; /* amount of space remaining for next write */
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index bae14438f869..472dc3b7d91f 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -336,6 +336,8 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
if (!skb)
goto maybe_error;
+ sp = rxrpc_skb(skb);
+ sp->rx_flags |= RXRPC_SKB_TX_BUFFER;
rxrpc_new_skb(skb, rxrpc_skb_tx_new);
_debug("ALLOC SEND %p", skb);
@@ -346,7 +348,6 @@ static int rxrpc_send_data(struct rxrpc_sock *rx,
skb_reserve(skb, call->conn->security_size);
skb->len += call->conn->security_size;
- sp = rxrpc_skb(skb);
sp->remain = chunk;
if (sp->remain > skb_tailroom(skb))
sp->remain = skb_tailroom(skb);
^ permalink raw reply related
* [PATCH net 3/9] rxrpc: Use info in skbuff instead of reparsing a jumbo packet
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Use the information now cached in the skbuff private data to avoid the need
to reparse a jumbo packet. We can find all the subpackets by dead
reckoning, so it's only necessary to note how many there are, whether the
last one is flagged as LAST_PACKET and whether any have the REQUEST_ACK
flag set.
This is necessary as once recvmsg() can see the packet, it can start
modifying it, such as doing in-place decryption.
Fixes: 248f219cb8bc ("rxrpc: Rewrite the data and ack handling code")
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/ar-internal.h | 3 -
net/rxrpc/input.c | 233 ++++++++++++++++++++++-------------------------
net/rxrpc/recvmsg.c | 41 +++++---
3 files changed, 135 insertions(+), 142 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 87cff6c218b6..20d7907a5bc6 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -617,8 +617,7 @@ struct rxrpc_call {
#define RXRPC_TX_ANNO_LAST 0x04
#define RXRPC_TX_ANNO_RESENT 0x08
-#define RXRPC_RX_ANNO_JUMBO 0x3f /* Jumbo subpacket number + 1 if not zero */
-#define RXRPC_RX_ANNO_JLAST 0x40 /* Set if last element of a jumbo packet */
+#define RXRPC_RX_ANNO_SUBPACKET 0x3f /* Subpacket number in jumbogram */
#define RXRPC_RX_ANNO_VERIFIED 0x80 /* Set if verified and decrypted */
rxrpc_seq_t tx_hard_ack; /* Dead slot in buffer; the first transmitted but
* not hard-ACK'd packet follows this.
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index b24492e5e429..140cede77655 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -405,10 +405,10 @@ static bool rxrpc_validate_data(struct sk_buff *skb)
* (that information is encoded in the ACK packet).
*/
static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
- u8 annotation, bool *_jumbo_bad)
+ bool is_jumbo, bool *_jumbo_bad)
{
/* Discard normal packets that are duplicates. */
- if (annotation == 0)
+ if (is_jumbo)
return;
/* Skip jumbo subpackets that are duplicates. When we've had three or
@@ -429,19 +429,17 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
enum rxrpc_call_state state;
- unsigned int offset = sizeof(struct rxrpc_wire_header);
- unsigned int ix;
+ unsigned int j;
rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
- rxrpc_seq_t seq0 = sp->hdr.seq, seq, hard_ack;
- bool immediate_ack = false, jumbo_bad = false, queued;
- u16 len;
- u8 ack = 0, flags, jumbo_flags, annotation = 0;
+ rxrpc_seq_t seq0 = sp->hdr.seq, hard_ack;
+ bool immediate_ack = false, jumbo_bad = false;
+ u8 ack = 0;
_enter("{%u,%u},{%u,%u}",
- call->rx_hard_ack, call->rx_top, skb->len, seq);
+ call->rx_hard_ack, call->rx_top, skb->len, seq0);
- _proto("Rx DATA %%%u { #%u f=%02x }",
- sp->hdr.serial, seq0, sp->hdr.flags);
+ _proto("Rx DATA %%%u { #%u f=%02x n=%u }",
+ sp->hdr.serial, seq0, sp->hdr.flags, sp->nr_subpackets);
state = READ_ONCE(call->state);
if (state >= RXRPC_CALL_COMPLETE) {
@@ -473,147 +471,136 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
goto unlock;
call->ackr_prev_seq = seq0;
- seq = seq0;
-
hard_ack = READ_ONCE(call->rx_hard_ack);
- if (after(seq, hard_ack + call->rx_winsize)) {
- ack = RXRPC_ACK_EXCEEDS_WINDOW;
- ack_serial = serial;
- goto ack;
- }
- flags = sp->hdr.flags;
- if (flags & RXRPC_JUMBO_PACKET) {
+ if (sp->nr_subpackets > 1) {
if (call->nr_jumbo_bad > 3) {
ack = RXRPC_ACK_NOSPACE;
ack_serial = serial;
goto ack;
}
- annotation = 1;
}
-next_subpacket:
- queued = false;
- ix = seq & RXRPC_RXTX_BUFF_MASK;
- len = skb->len;
- if (flags & RXRPC_JUMBO_PACKET)
- len = RXRPC_JUMBO_DATALEN;
-
- if (flags & RXRPC_LAST_PACKET) {
- if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
- seq != call->rx_top) {
- rxrpc_proto_abort("LSN", call, seq);
- goto unlock;
+ for (j = 0; j < sp->nr_subpackets; j++) {
+ rxrpc_serial_t serial = sp->hdr.serial + j;
+ rxrpc_seq_t seq = seq0 + j;
+ unsigned int ix = seq & RXRPC_RXTX_BUFF_MASK;
+ bool terminal = (j == sp->nr_subpackets - 1);
+ bool last = terminal && (sp->rx_flags & RXRPC_SKB_INCL_LAST);
+ u8 flags, annotation = j;
+
+ _proto("Rx DATA+%u %%%u { #%x t=%u l=%u }",
+ j, serial, seq, terminal, last);
+
+ if (last) {
+ if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
+ seq != call->rx_top) {
+ rxrpc_proto_abort("LSN", call, seq);
+ goto unlock;
+ }
+ } else {
+ if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
+ after_eq(seq, call->rx_top)) {
+ rxrpc_proto_abort("LSA", call, seq);
+ goto unlock;
+ }
}
- } else {
- if (test_bit(RXRPC_CALL_RX_LAST, &call->flags) &&
- after_eq(seq, call->rx_top)) {
- rxrpc_proto_abort("LSA", call, seq);
- goto unlock;
+
+ flags = 0;
+ if (last)
+ flags |= RXRPC_LAST_PACKET;
+ if (!terminal)
+ flags |= RXRPC_JUMBO_PACKET;
+ if (test_bit(j, sp->rx_req_ack))
+ flags |= RXRPC_REQUEST_ACK;
+ trace_rxrpc_rx_data(call->debug_id, seq, serial, flags, annotation);
+
+ if (before_eq(seq, hard_ack)) {
+ ack = RXRPC_ACK_DUPLICATE;
+ ack_serial = serial;
+ continue;
}
- }
- trace_rxrpc_rx_data(call->debug_id, seq, serial, flags, annotation);
- if (before_eq(seq, hard_ack)) {
- ack = RXRPC_ACK_DUPLICATE;
- ack_serial = serial;
- goto skip;
- }
+ if (call->rxtx_buffer[ix]) {
+ rxrpc_input_dup_data(call, seq, sp->nr_subpackets > 1,
+ &jumbo_bad);
+ if (ack != RXRPC_ACK_DUPLICATE) {
+ ack = RXRPC_ACK_DUPLICATE;
+ ack_serial = serial;
+ }
+ immediate_ack = true;
+ continue;
+ }
- if (flags & RXRPC_REQUEST_ACK && !ack) {
- ack = RXRPC_ACK_REQUESTED;
- ack_serial = serial;
- }
+ if (after(seq, hard_ack + call->rx_winsize)) {
+ ack = RXRPC_ACK_EXCEEDS_WINDOW;
+ ack_serial = serial;
+ if (flags & RXRPC_JUMBO_PACKET) {
+ if (!jumbo_bad) {
+ call->nr_jumbo_bad++;
+ jumbo_bad = true;
+ }
+ }
- if (call->rxtx_buffer[ix]) {
- rxrpc_input_dup_data(call, seq, annotation, &jumbo_bad);
- if (ack != RXRPC_ACK_DUPLICATE) {
- ack = RXRPC_ACK_DUPLICATE;
+ goto ack;
+ }
+
+ if (flags & RXRPC_REQUEST_ACK && !ack) {
+ ack = RXRPC_ACK_REQUESTED;
ack_serial = serial;
}
- immediate_ack = true;
- goto skip;
- }
- /* Queue the packet. We use a couple of memory barriers here as need
- * to make sure that rx_top is perceived to be set after the buffer
- * pointer and that the buffer pointer is set after the annotation and
- * the skb data.
- *
- * Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
- * and also rxrpc_fill_out_ack().
- */
- if (flags & RXRPC_JUMBO_PACKET) {
- rxrpc_get_skb(skb, rxrpc_skb_rx_got);
- if (skb_copy_bits(skb, offset, &jumbo_flags, 1) < 0) {
- rxrpc_proto_abort("XJF", call, seq);
- goto unlock;
+ /* Queue the packet. We use a couple of memory barriers here as need
+ * to make sure that rx_top is perceived to be set after the buffer
+ * pointer and that the buffer pointer is set after the annotation and
+ * the skb data.
+ *
+ * Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
+ * and also rxrpc_fill_out_ack().
+ */
+ if (!terminal)
+ rxrpc_get_skb(skb, rxrpc_skb_rx_got);
+ call->rxtx_annotations[ix] = annotation;
+ smp_wmb();
+ call->rxtx_buffer[ix] = skb;
+ if (after(seq, call->rx_top)) {
+ smp_store_release(&call->rx_top, seq);
+ } else if (before(seq, call->rx_top)) {
+ /* Send an immediate ACK if we fill in a hole */
+ if (!ack) {
+ ack = RXRPC_ACK_DELAY;
+ ack_serial = serial;
+ }
+ immediate_ack = true;
}
- }
- call->rxtx_annotations[ix] = annotation;
- smp_wmb();
- call->rxtx_buffer[ix] = skb;
- if (after(seq, call->rx_top)) {
- smp_store_release(&call->rx_top, seq);
- if (!(flags & RXRPC_JUMBO_PACKET)) {
+
+ if (terminal) {
/* From this point on, we're not allowed to touch the
* packet any longer as its ref now belongs to the Rx
* ring.
*/
skb = NULL;
}
- } else if (before(seq, call->rx_top)) {
- /* Send an immediate ACK if we fill in a hole */
- if (!ack) {
- ack = RXRPC_ACK_DELAY;
- ack_serial = serial;
- }
- immediate_ack = true;
- }
- if (flags & RXRPC_LAST_PACKET) {
- set_bit(RXRPC_CALL_RX_LAST, &call->flags);
- trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq);
- } else {
- trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq);
- }
- queued = true;
- if (after_eq(seq, call->rx_expect_next)) {
- if (after(seq, call->rx_expect_next)) {
- _net("OOS %u > %u", seq, call->rx_expect_next);
- ack = RXRPC_ACK_OUT_OF_SEQUENCE;
- ack_serial = serial;
+ if (last) {
+ set_bit(RXRPC_CALL_RX_LAST, &call->flags);
+ if (!ack) {
+ ack = RXRPC_ACK_DELAY;
+ ack_serial = serial;
+ }
+ trace_rxrpc_receive(call, rxrpc_receive_queue_last, serial, seq);
+ } else {
+ trace_rxrpc_receive(call, rxrpc_receive_queue, serial, seq);
}
- call->rx_expect_next = seq + 1;
- }
-skip:
- offset += len;
- if (flags & RXRPC_JUMBO_PACKET) {
- flags = jumbo_flags;
- offset += sizeof(struct rxrpc_jumbo_header);
- seq++;
- serial++;
- annotation++;
- if (flags & RXRPC_JUMBO_PACKET)
- annotation |= RXRPC_RX_ANNO_JLAST;
- if (after(seq, hard_ack + call->rx_winsize)) {
- ack = RXRPC_ACK_EXCEEDS_WINDOW;
- ack_serial = serial;
- if (!jumbo_bad) {
- call->nr_jumbo_bad++;
- jumbo_bad = true;
+ if (after_eq(seq, call->rx_expect_next)) {
+ if (after(seq, call->rx_expect_next)) {
+ _net("OOS %u > %u", seq, call->rx_expect_next);
+ ack = RXRPC_ACK_OUT_OF_SEQUENCE;
+ ack_serial = serial;
}
- goto ack;
+ call->rx_expect_next = seq + 1;
}
-
- _proto("Rx DATA Jumbo %%%u", serial);
- goto next_subpacket;
- }
-
- if (queued && flags & RXRPC_LAST_PACKET && !ack) {
- ack = RXRPC_ACK_DELAY;
- ack_serial = serial;
}
ack:
diff --git a/net/rxrpc/recvmsg.c b/net/rxrpc/recvmsg.c
index 9a7e1bc9791d..e49eacfaf4d6 100644
--- a/net/rxrpc/recvmsg.c
+++ b/net/rxrpc/recvmsg.c
@@ -177,7 +177,8 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
struct sk_buff *skb;
rxrpc_serial_t serial;
rxrpc_seq_t hard_ack, top;
- u8 flags;
+ bool last = false;
+ u8 subpacket;
int ix;
_enter("%d", call->debug_id);
@@ -191,10 +192,13 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
skb = call->rxtx_buffer[ix];
rxrpc_see_skb(skb, rxrpc_skb_rx_rotated);
sp = rxrpc_skb(skb);
- flags = sp->hdr.flags;
- serial = sp->hdr.serial;
- if (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO)
- serial += (call->rxtx_annotations[ix] & RXRPC_RX_ANNO_JUMBO) - 1;
+
+ subpacket = call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET;
+ serial = sp->hdr.serial + subpacket;
+
+ if (subpacket == sp->nr_subpackets - 1 &&
+ sp->rx_flags & RXRPC_SKB_INCL_LAST)
+ last = true;
call->rxtx_buffer[ix] = NULL;
call->rxtx_annotations[ix] = 0;
@@ -203,9 +207,8 @@ static void rxrpc_rotate_rx_window(struct rxrpc_call *call)
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
- _debug("%u,%u,%02x", hard_ack, top, flags);
trace_rxrpc_receive(call, rxrpc_receive_rotate, serial, hard_ack);
- if (flags & RXRPC_LAST_PACKET) {
+ if (last) {
rxrpc_end_rx_phase(call, serial);
} else {
/* Check to see if there's an ACK that needs sending. */
@@ -233,18 +236,19 @@ static int rxrpc_verify_packet(struct rxrpc_call *call, struct sk_buff *skb,
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
rxrpc_seq_t seq = sp->hdr.seq;
u16 cksum = sp->hdr.cksum;
+ u8 subpacket = annotation & RXRPC_RX_ANNO_SUBPACKET;
_enter("");
/* For all but the head jumbo subpacket, the security checksum is in a
* jumbo header immediately prior to the data.
*/
- if ((annotation & RXRPC_RX_ANNO_JUMBO) > 1) {
+ if (subpacket > 0) {
__be16 tmp;
if (skb_copy_bits(skb, offset - 2, &tmp, 2) < 0)
BUG();
cksum = ntohs(tmp);
- seq += (annotation & RXRPC_RX_ANNO_JUMBO) - 1;
+ seq += subpacket;
}
return call->conn->security->verify_packet(call, skb, offset, len,
@@ -265,19 +269,18 @@ static int rxrpc_locate_data(struct rxrpc_call *call, struct sk_buff *skb,
u8 *_annotation,
unsigned int *_offset, unsigned int *_len)
{
+ struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
unsigned int offset = sizeof(struct rxrpc_wire_header);
unsigned int len;
int ret;
u8 annotation = *_annotation;
+ u8 subpacket = annotation & RXRPC_RX_ANNO_SUBPACKET;
/* Locate the subpacket */
+ offset += subpacket * RXRPC_JUMBO_SUBPKTLEN;
len = skb->len - offset;
- if ((annotation & RXRPC_RX_ANNO_JUMBO) > 0) {
- offset += (((annotation & RXRPC_RX_ANNO_JUMBO) - 1) *
- RXRPC_JUMBO_SUBPKTLEN);
- len = (annotation & RXRPC_RX_ANNO_JLAST) ?
- skb->len - offset : RXRPC_JUMBO_SUBPKTLEN;
- }
+ if (subpacket < sp->nr_subpackets - 1)
+ len = RXRPC_JUMBO_DATALEN;
if (!(annotation & RXRPC_RX_ANNO_VERIFIED)) {
ret = rxrpc_verify_packet(call, skb, annotation, offset, len);
@@ -303,6 +306,7 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
{
struct rxrpc_skb_priv *sp;
struct sk_buff *skb;
+ rxrpc_serial_t serial;
rxrpc_seq_t hard_ack, top, seq;
size_t remain;
bool last;
@@ -339,9 +343,12 @@ static int rxrpc_recvmsg_data(struct socket *sock, struct rxrpc_call *call,
rxrpc_see_skb(skb, rxrpc_skb_rx_seen);
sp = rxrpc_skb(skb);
- if (!(flags & MSG_PEEK))
+ if (!(flags & MSG_PEEK)) {
+ serial = sp->hdr.serial;
+ serial += call->rxtx_annotations[ix] & RXRPC_RX_ANNO_SUBPACKET;
trace_rxrpc_receive(call, rxrpc_receive_front,
- sp->hdr.serial, seq);
+ serial, seq);
+ }
if (msg)
sock_recv_timestamp(msg, sock->sk, skb);
^ permalink raw reply related
* [PATCH net 2/9] rxrpc: Improve jumbo packet counting
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Improve the information stored about jumbo packets so that we don't need to
reparse them so much later.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
---
net/rxrpc/ar-internal.h | 10 +++++++---
net/rxrpc/input.c | 23 ++++++++++++++---------
net/rxrpc/protocol.h | 9 +++++++++
3 files changed, 30 insertions(+), 12 deletions(-)
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 145335611af6..87cff6c218b6 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -185,11 +185,15 @@ struct rxrpc_host_header {
* - max 48 bytes (struct sk_buff::cb)
*/
struct rxrpc_skb_priv {
- union {
- u8 nr_jumbo; /* Number of jumbo subpackets */
- };
+ u8 nr_subpackets; /* Number of subpackets */
+ u8 rx_flags; /* Received packet flags */
+#define RXRPC_SKB_INCL_LAST 0x01 /* - Includes last packet */
union {
int remain; /* amount of space remaining for next write */
+
+ /* List of requested ACKs on subpackets */
+ unsigned long rx_req_ack[(RXRPC_MAX_NR_JUMBO + BITS_PER_LONG - 1) /
+ BITS_PER_LONG];
};
struct rxrpc_host_header hdr; /* RxRPC packet header from this packet */
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index 5789ec5ad54f..b24492e5e429 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -347,7 +347,7 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
}
/*
- * Scan a jumbo packet to validate its structure and to work out how many
+ * Scan a data packet to validate its structure and to work out how many
* subpackets it contains.
*
* A jumbo packet is a collection of consecutive packets glued together with
@@ -358,16 +358,21 @@ static bool rxrpc_receiving_reply(struct rxrpc_call *call)
* the last are RXRPC_JUMBO_DATALEN in size. The last subpacket may be of any
* size.
*/
-static bool rxrpc_validate_jumbo(struct sk_buff *skb)
+static bool rxrpc_validate_data(struct sk_buff *skb)
{
struct rxrpc_skb_priv *sp = rxrpc_skb(skb);
unsigned int offset = sizeof(struct rxrpc_wire_header);
unsigned int len = skb->len;
- int nr_jumbo = 1;
u8 flags = sp->hdr.flags;
- do {
- nr_jumbo++;
+ for (;;) {
+ if (flags & RXRPC_REQUEST_ACK)
+ __set_bit(sp->nr_subpackets, sp->rx_req_ack);
+ sp->nr_subpackets++;
+
+ if (!(flags & RXRPC_JUMBO_PACKET))
+ break;
+
if (len - offset < RXRPC_JUMBO_SUBPKTLEN)
goto protocol_error;
if (flags & RXRPC_LAST_PACKET)
@@ -376,9 +381,10 @@ static bool rxrpc_validate_jumbo(struct sk_buff *skb)
if (skb_copy_bits(skb, offset, &flags, 1) < 0)
goto protocol_error;
offset += sizeof(struct rxrpc_jumbo_header);
- } while (flags & RXRPC_JUMBO_PACKET);
+ }
- sp->nr_jumbo = nr_jumbo;
+ if (flags & RXRPC_LAST_PACKET)
+ sp->rx_flags |= RXRPC_SKB_INCL_LAST;
return true;
protocol_error:
@@ -1254,8 +1260,7 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
if (sp->hdr.callNumber == 0 ||
sp->hdr.seq == 0)
goto bad_message;
- if (sp->hdr.flags & RXRPC_JUMBO_PACKET &&
- !rxrpc_validate_jumbo(skb))
+ if (!rxrpc_validate_data(skb))
goto bad_message;
break;
diff --git a/net/rxrpc/protocol.h b/net/rxrpc/protocol.h
index 99ce322d7caa..49bb972539aa 100644
--- a/net/rxrpc/protocol.h
+++ b/net/rxrpc/protocol.h
@@ -89,6 +89,15 @@ struct rxrpc_jumbo_header {
#define RXRPC_JUMBO_DATALEN 1412 /* non-terminal jumbo packet data length */
#define RXRPC_JUMBO_SUBPKTLEN (RXRPC_JUMBO_DATALEN + sizeof(struct rxrpc_jumbo_header))
+/*
+ * The maximum number of subpackets that can possibly fit in a UDP packet is:
+ *
+ * ((max_IP - IP_hdr - UDP_hdr) / RXRPC_JUMBO_SUBPKTLEN) + 1
+ * = ((65535 - 28 - 28) / 1416) + 1
+ * = 46 non-terminal packets and 1 terminal packet.
+ */
+#define RXRPC_MAX_NR_JUMBO 47
+
/*****************************************************************************/
/*
* on-the-wire Rx ACK packet data payload
^ permalink raw reply related
* [PATCH net 1/9] rxrpc: Pass the input handler's data skb reference to the Rx ring
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
In-Reply-To: <156647659913.11061.13764606104739742865.stgit@warthog.procyon.org.uk>
Pass the reference held on a DATA skb in the rxrpc input handler into the
Rx ring rather than getting an additional ref for this and then dropping
the original ref at the end.
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/input.c | 48 ++++++++++++++++++++++++++++++++++--------------
1 file changed, 34 insertions(+), 14 deletions(-)
diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index dd47d465d1d3..5789ec5ad54f 100644
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -416,7 +416,8 @@ static void rxrpc_input_dup_data(struct rxrpc_call *call, rxrpc_seq_t seq,
}
/*
- * Process a DATA packet, adding the packet to the Rx ring.
+ * Process a DATA packet, adding the packet to the Rx ring. The caller's
+ * packet ref must be passed on or discarded.
*/
static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
{
@@ -425,20 +426,22 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
unsigned int offset = sizeof(struct rxrpc_wire_header);
unsigned int ix;
rxrpc_serial_t serial = sp->hdr.serial, ack_serial = 0;
- rxrpc_seq_t seq = sp->hdr.seq, hard_ack;
+ rxrpc_seq_t seq0 = sp->hdr.seq, seq, hard_ack;
bool immediate_ack = false, jumbo_bad = false, queued;
u16 len;
- u8 ack = 0, flags, annotation = 0;
+ u8 ack = 0, flags, jumbo_flags, annotation = 0;
_enter("{%u,%u},{%u,%u}",
call->rx_hard_ack, call->rx_top, skb->len, seq);
_proto("Rx DATA %%%u { #%u f=%02x }",
- sp->hdr.serial, seq, sp->hdr.flags);
+ sp->hdr.serial, seq0, sp->hdr.flags);
state = READ_ONCE(call->state);
- if (state >= RXRPC_CALL_COMPLETE)
+ if (state >= RXRPC_CALL_COMPLETE) {
+ rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
return;
+ }
if (call->state == RXRPC_CALL_SERVER_RECV_REQUEST) {
unsigned long timo = READ_ONCE(call->next_req_timo);
@@ -463,7 +466,8 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
!rxrpc_receiving_reply(call))
goto unlock;
- call->ackr_prev_seq = seq;
+ call->ackr_prev_seq = seq0;
+ seq = seq0;
hard_ack = READ_ONCE(call->rx_hard_ack);
if (after(seq, hard_ack + call->rx_winsize)) {
@@ -533,12 +537,25 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
* Barriers against rxrpc_recvmsg_data() and rxrpc_rotate_rx_window()
* and also rxrpc_fill_out_ack().
*/
- rxrpc_get_skb(skb, rxrpc_skb_rx_got);
+ if (flags & RXRPC_JUMBO_PACKET) {
+ rxrpc_get_skb(skb, rxrpc_skb_rx_got);
+ if (skb_copy_bits(skb, offset, &jumbo_flags, 1) < 0) {
+ rxrpc_proto_abort("XJF", call, seq);
+ goto unlock;
+ }
+ }
call->rxtx_annotations[ix] = annotation;
smp_wmb();
call->rxtx_buffer[ix] = skb;
if (after(seq, call->rx_top)) {
smp_store_release(&call->rx_top, seq);
+ if (!(flags & RXRPC_JUMBO_PACKET)) {
+ /* From this point on, we're not allowed to touch the
+ * packet any longer as its ref now belongs to the Rx
+ * ring.
+ */
+ skb = NULL;
+ }
} else if (before(seq, call->rx_top)) {
/* Send an immediate ACK if we fill in a hole */
if (!ack) {
@@ -567,10 +584,7 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
skip:
offset += len;
if (flags & RXRPC_JUMBO_PACKET) {
- if (skb_copy_bits(skb, offset, &flags, 1) < 0) {
- rxrpc_proto_abort("XJF", call, seq);
- goto unlock;
- }
+ flags = jumbo_flags;
offset += sizeof(struct rxrpc_jumbo_header);
seq++;
serial++;
@@ -606,13 +620,14 @@ static void rxrpc_input_data(struct rxrpc_call *call, struct sk_buff *skb)
false, true,
rxrpc_propose_ack_input_data);
- if (sp->hdr.seq == READ_ONCE(call->rx_hard_ack) + 1) {
+ if (seq0 == READ_ONCE(call->rx_hard_ack) + 1) {
trace_rxrpc_notify_socket(call->debug_id, serial);
rxrpc_notify_socket(call);
}
unlock:
spin_unlock(&call->input_lock);
+ rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
_leave(" [queued]");
}
@@ -1021,7 +1036,7 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call,
switch (sp->hdr.type) {
case RXRPC_PACKET_TYPE_DATA:
rxrpc_input_data(call, skb);
- break;
+ goto no_free;
case RXRPC_PACKET_TYPE_ACK:
rxrpc_input_ack(call, skb);
@@ -1048,6 +1063,8 @@ static void rxrpc_input_call_packet(struct rxrpc_call *call,
break;
}
+ rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
+no_free:
_leave("");
}
@@ -1373,8 +1390,11 @@ int rxrpc_input_packet(struct sock *udp_sk, struct sk_buff *skb)
mutex_unlock(&call->user_mutex);
}
+ /* Process a call packet; this either discards or passes on the ref
+ * elsewhere.
+ */
rxrpc_input_call_packet(call, skb);
- goto discard;
+ goto out;
discard:
rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
^ permalink raw reply related
* [PATCH net 0/9] rxrpc: Fix use of skb_cow_data()
From: David Howells @ 2019-08-22 12:23 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
Here's a series of patches that fixes the use of skb_cow_data() in rxrpc.
The problem is that skb_cow_data() indirectly requires that the maximum
usage count on an sk_buff be 1, and it may generate an assertion failure in
pskb_expand_head() if not.
This can occur because rxrpc_input_data() may be still holding a ref when
it has just attached the sk_buff to the rx ring and given that attachment
its own ref. If recvmsg happens fast enough, skb_cow_data() can see the
ref still held by the softirq handler.
Further, a packet may contain multiple subpackets, each of which gets its
own attachment to the ring and its own ref - also making skb_cow_data() go
bang.
Fix this by:
(1) The DATA packet is currently parsed for subpackets twice by the input
routines. Parse it just once instead and make notes in the sk_buff
private data.
(2) Use the notes from (1) when attaching the packet to the ring multiple
times. Once the packet is attached to the ring, recvmsg can see it
and cow it and start modifying it, so the softirq handler is not
permitted to look inside it from that point.
(3) Stick a second reference count in the skb private data, in struct
rxrpc_skb_priv, to count the refs held by the ring on the packet. All
these refs together hold one single ref on the sk_buff main ref
counter.
(4) Pass the ref from the input code to the ring rather than getting an
extra ref. rxrpc_input_data() uses a ref on the second refcount to
prevent the packet from evaporating under it.
(5) rxkad currently calls skb_cow_data() once for each subpacket it needs
to decrypt. It should only be calling this once, however, so move
that into recvmsg and only do it when we first see a new packet.
There's also a patch to improve the rxrpc_skb tracepoint to make sure that
Tx-derived buffers are identified separately from Rx-derived buffers in the
trace.
Tested-by: Marc Dionne <marc.dionne@auristor.com>
The patches are tagged here:
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
rxrpc-fixes-20190820
and can also be found on the following branch:
http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=rxrpc-fixes
David
---
David Howells (9):
rxrpc: Pass the input handler's data skb reference to the Rx ring
rxrpc: Improve jumbo packet counting
rxrpc: Use info in skbuff instead of reparsing a jumbo packet
rxrpc: Add a private skb flag to indicate transmission-phase skbs
rxrpc: Abstract out rxtx ring cleanup
rxrpc: Use the tx-phase skb flag to simplify tracing
rxrpc: Add a shadow refcount in the skb private data
rxrpc: Use shadow refcount for packets in the RxTx ring
rxrpc: Only call skb_cow_data() once per packet
include/trace/events/rxrpc.h | 62 +++++----
net/rxrpc/ar-internal.h | 18 ++-
net/rxrpc/call_event.c | 8 +
net/rxrpc/call_object.c | 33 ++---
net/rxrpc/conn_event.c | 6 -
net/rxrpc/input.c | 285 ++++++++++++++++++++++--------------------
net/rxrpc/local_event.c | 4 -
net/rxrpc/output.c | 6 -
net/rxrpc/peer_event.c | 10 +
net/rxrpc/protocol.h | 9 +
net/rxrpc/recvmsg.c | 58 +++++----
net/rxrpc/rxkad.c | 32 +----
net/rxrpc/sendmsg.c | 14 +-
net/rxrpc/skbuff.c | 72 +++++++++--
14 files changed, 348 insertions(+), 269 deletions(-)
^ permalink raw reply
* [PATCH net 0/9] rxrpc: Fix use of skb_cow_data()
From: David Howells @ 2019-08-22 12:22 UTC (permalink / raw)
To: netdev; +Cc: dhowells, linux-afs, linux-kernel
Here's a series of patches that fixes the use of skb_cow_data() in rxrpc.
The problem is that skb_cow_data() indirectly requires that the maximum
usage count on an sk_buff be 1, and it may generate an assertion failure in
pskb_expand_head() if not.
This can occur because rxrpc_input_data() may be still holding a ref when
it has just attached the sk_buff to the rx ring and given that attachment
its own ref. If recvmsg happens fast enough, skb_cow_data() can see the
ref still held by the softirq handler.
Further, a packet may contain multiple subpackets, each of which gets its
own attachment to the ring and its own ref - also making skb_cow_data() go
bang.
Fix this by:
(1) The DATA packet is currently parsed for subpackets twice by the input
routines. Parse it just once instead and make notes in the sk_buff
private data.
(2) Use the notes from (1) when attaching the packet to the ring multiple
times. Once the packet is attached to the ring, recvmsg can see it
and cow it and start modifying it, so the softirq handler is not
permitted to look inside it from that point.
(3) Stick a second reference count in the skb private data, in struct
rxrpc_skb_priv, to count the refs held by the ring on the packet. All
these refs together hold one single ref on the sk_buff main ref
counter.
(4) Pass the ref from the input code to the ring rather than getting an
extra ref. rxrpc_input_data() uses a ref on the second refcount to
prevent the packet from evaporating under it.
(5) rxkad currently calls skb_cow_data() once for each subpacket it needs
to decrypt. It should only be calling this once, however, so move
that into recvmsg and only do it when we first see a new packet.
There's also a patch to improve the rxrpc_skb tracepoint to make sure that
Tx-derived buffers are identified separately from Rx-derived buffers in the
trace.
The patches are tagged here:
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
rxrpc-fixes-20190820
and can also be found on the following branch:
http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=rxrpc-fixes
David
---
David Howells (9):
rxrpc: Pass the input handler's data skb reference to the Rx ring
rxrpc: Improve jumbo packet counting
rxrpc: Use info in skbuff instead of reparsing a jumbo packet
rxrpc: Add a private skb flag to indicate transmission-phase skbs
rxrpc: Abstract out rxtx ring cleanup
rxrpc: Use the tx-phase skb flag to simplify tracing
rxrpc: Add a shadow refcount in the skb private data
rxrpc: Use shadow refcount for packets in the RxTx ring
rxrpc: Only call skb_cow_data() once per packet
include/trace/events/rxrpc.h | 62 +++++----
net/rxrpc/ar-internal.h | 18 ++-
net/rxrpc/call_event.c | 8 +
net/rxrpc/call_object.c | 33 ++---
net/rxrpc/conn_event.c | 6 -
net/rxrpc/input.c | 285 ++++++++++++++++++++++--------------------
net/rxrpc/local_event.c | 4 -
net/rxrpc/output.c | 6 -
net/rxrpc/peer_event.c | 10 +
net/rxrpc/protocol.h | 9 +
net/rxrpc/recvmsg.c | 58 +++++----
net/rxrpc/rxkad.c | 32 +----
net/rxrpc/sendmsg.c | 14 +-
net/rxrpc/skbuff.c | 72 +++++++++--
14 files changed, 348 insertions(+), 269 deletions(-)
^ permalink raw reply
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